Simple Low Power Switching Regulator Circuit Diagram

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This is the Simple Low Power Switching Regulator Circuit Diagram. A simple battery-powered switching regulator provides 5 V out from a 9-V source with 80% efficiency and 50 mA output capability. When Q1 is on, its collector voltage rises, forcing current through the inductor. The output voltage rises, causing A1`s output to rise. 



Simple Low Power Switching Regulator Circuit Diagram

Q1 cuts off and the output decays through the load. The 100-pF capacitor ensures clean switching. The cycle repeats when the output drops1ow enough for A1 to turn on Ql. The 1-
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Build a Power supply Protection Circuit Diagram

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Why Build a Power supply Protection Circuit Diagram. When using a regulated supply to reduce a supply voltage there is always the danger of component failure in the supply and consequent damage to the equipment. A fuse will protect when excess current is drawn, but might be too slow to cope with over voltage conditions. The values shown are for a 12 V supply being dropped to 5 V.

Power supply Protection Circuit Diagram

Power supply Protection Circuit Diagram


The trip voltage is set to 5.7 V to protect the equipment in the event of a regulator fault. The 330 ohm resistor and the 500 ohm potentiometer form a potential divider which samples the output voltage as set by adjustment of the potentiometer. The SCR is selected to carry at least twice the fuse rating. The full supply voltage is connected to the input of the regulator.

The 2N2906 is held bias off by the 10 k resistor and the SCR so that the LED is held off. If the output voltage rises above a set trip value then the SCR will conduct, the fuse will blow, and the 2N3906 will be supplied with base current via the 10 k resistor, and the LED will light up.
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Memory Save on Power down Circuit Diagram

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Memory Save on Power down Circuit Diagram. The auxiliary output powers the memory, while the main output powers the system and is connected to the memory store pin. When power goes down, the main output goes low, commanding the memory to store. The auxiliary output then drops out.


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Simple Relay Fuse For Battery Charges Circuit Diagram

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This is a Simple Relay Fuse For Battery Charges Circuit Diagram. Charged capacitor C3 and momentary pushbutton switch S2 are used to momentarily energize relay RE 2. The batteiy under charge energizes the relay to hold it closed. S2 will energize the relay even if the battery is too far discharged initially to energize it.

Relay Fuse For Battery Charges Circuit Diagram

Simple Relay Fuse For Battery Charges Circuit Diagram

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Off line Fly back Regulator Circuit Diagram

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This Off line Fly back Regulator Circuit Diagram uses a low-cost feedback scheme in which the dc voltage developed from the primary-side control winding is sensed by the UC1842 error amplifier. Load regulation is therefore dependent on the j coupling between secondary and control windings, and on transformer leakage inductance. 

For applications requiring better load regulation, a UC1901 Isolated Feedback Generator can be used to directly sense the output voltage.

Off line Fly back Regulator Circuit Diagram

Off line Fly back Regulator Circuit Diagram

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Single Supply fault Monitor Circuit Diagram

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This Single Supply fault Monitor Circuit Diagram shows a typical over/under-voltage fault monitor for a single supply. The upper trip points, controlling OUT 1, are centered on 5.5 V with 100 mY of hysteresis Wu = 5.55 V, `L = 5.45 V); and the lower trip points, controlling OUT 2, are centered on 4.5 V, also with 100 mV of hysteresis. OUT 1 and OUT 2 are connected together in a wired OR configuration to generate a power OK signal.


Single Supply fault Monitor Circuit Diagram

Single Supply fault Monitor Circuit Diagram

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Low power Dc-Dc Converter Circuit Diagram

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This low-power converter will supply about 100 mW of dc to a load and it is useful to isolate or derive dc voltages. It operates at around 200 kHz. LI is wound on a 22-mm diameter 13-mm high pot core with #32 magnet wire. The primary is 80 turns and the secondary is 80 turns (for 12- V nominal output). The two windings should be insulated for the expected voltage difference between input and output in insulation applications. 


Low power Dc-Dc Converter Circuit Diagram

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Simple 250W Inverter Circuit Diagram

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This is a simple 250W Inverter Circuit Diagram. A 555 timer (IC1) generates a 120-Hz signal that is fed to a CD4013BE flip-flop (ICl-a), which divides the input frequency by two to generate a 60-Hz clocking frequency for the FET array (Ql through Q6). Transformer Tl is a 12-/24-V center-tapped 60-Hz transformer of suitable size. 

250W Inverter Circuit Diagram

250W Inverter Circuit Diagram

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High-Voltage Pulse Supply Circuit Diagram

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This high-voltage pulse supply will generate pulses up to 30 kV. Ql and Q2 form a multivibrator in conjunction with peripheral components Rl through R6 and CI, C2, C3, C5, C6, and D2. R9 adjusts the pulse repetition rate. R2 should be selected to limit the maximum repetition rate to 20 Hz. II is a type 1156 lamp used as a current limiter. 

R9 can be left out and R2 selected to produce a fixed rate, if desired. Try about 1 as a start. Q3 serves as a power amplifier and switch to drive Tl (an automotive ignition coil). NE1 is used as a pulse indicator and indicates circuit operation. Because this circuit can develop up to 30 kV, suitable construction techniques and safety precautions should be observed.



High-Voltage Pulse Supply Circuit Diagram

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The High Voltage Geiger Counter Supply Circuit Diagram

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This High Voltage Geiger Counter Supply Circuit Diagram will generate about 300 volts dc —at a very low current, but enough for a GM tube. be careful with the output.


High Voltage Geiger Counter Supply Circuit Diagram

High Voltage Geiger Counter Supply Circuit Diagram

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Build a Low Power Consumption 5V Regulator Circuit Diagram

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How to build a Low Power Consumption 5V Regulator Circuit Diagram? The special feature of the circuit shown below is the low consumption. With voltage n 9 at the entrance and no exit load, absorbs current 50 ma, which is certainly very small compared with a quiescent current 78L05. The components that comprise it are scarce. Just a reference voltage source, formed by the T1 and the IC 1 and an amplifier consisting of the IC2 and T2 so we have to output the desired voltage stabilizer. 

The trend that emerges at the output of IC 1 increased to 1,22 V. Using the IC2 and the P1 is set so that the output of the circuit is n equal to 5 exactly at the entrance of the circuit can be imposed voltage between 6.5 ??? 30 V DC, while the maximum output current reaches 1 mA for the better functioning of the stabilizer, transistors T and T 1 a 1 b should be possible similar characteristics. That is why we preferred a 'double' type transistors MAT02 or alternatively one of the MAT01, SSM2210 or LM394. 

 Low Power Consumption 5V Regulator Circuit Diagram

Low Power Consumption 5V Regulator Circuit Diagram

If your course is hard to find, you can use two common BC, but which should be selected to have approximately the same threshold voltage. The Operational IC 1 and IC2 is type OR22. Especially for IC2, the peak current of the output can be set using the power introduced in this through the resistor R9. The price of electricity varies between 500 to 400 ma BAC course, before making an increase, you should check whether the output transistor T2 is able to meet the equally elevated currents that it may request the load. 

The filter formed by the R6-C 1 is meant to suppress the spurious peaks may accidentally be deployed at the entrance of IC2. The capacitor C2 improves the stability of the circuit, wherethose which the stabilizer is required to provide pulsed current. The total circuit resistance and is highly therefore sensitive to any kind of electrostatic and magnetic disturbances. The control stabilizer made with a complex load to absorb continuous stream of 1 mA. The pulse of 1 mA Measurement results are shown in the table. The current Ig represents the quiescent current of stabilizer.
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Simple Bilateral Current Source Circuit Diagram

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The Simple Bilateral Current Source Circuit Diagram will produce the current relationship to within 2% using 1% values for Rl through R5. This includes variations in Rl from 100 ohm to 2000 ohm. The use of large resistors for Rl through R4 minimizes the error due to Rl variations. The large resistors are possible because of the excellent input bias current performance of the OP-08,.

Simple Bilateral Current Source Circuit Diagram

Simple Bilateral Current Source Circuit Diagram

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Shift Register Driver Power Supply Circuit Diagram

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This is the Shift Register Driver Power Supply Circuit Diagram. A16 V power supply can be synthesized as shown using IN1692 rectifiers. A shift pulse input saturates the 2N2714 depriving the Darling-ton combination (2N2714 and 2N2868) of base drive.The negative pulse so generated on the 15 V line is differentiated to produce a positive trigger pulse at its trailing edge.

Shift Register Driver Power Supply Circuit Diagram

Shift Register Driver Power Supply Circuit Diagram

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Simple Self Oscillating Switching Converter Circuit Diagram

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This is a Simple Self Oscillating Switching Converter Circuit Diagram. Regulation is provided by taking the rectified output of the sense winding and applying it as a bias to the base of Q2 via zener Dl. The collector of Q2 then removes drive from the gate of Ql. 

Therefore, if the . output voltage should increase, Q2 removes the drive to Ql earlier, shortening the on time, and the output voltage will remain the same. De outputs are obtained by merely rectifying and filtering secondary windings, as done by D5 and C4.

Self Oscillating Switching Converter Circuit Diagram

Simple Self Oscillating Switching Converter Circuit Diagram

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Build a Positive input Negative output Charge pump Circuit Diagram

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How to Build a Positive input Negative output Charge pump Circuit Diagram. A simple means of generating a low-power voltage supply of opposite polarity from the main supply. Self oscillating driver produces pulses at a repetition frequency of 100 kHz. 

When the VMOS device is off, capacitor C is charged to the positive supply. When the VMOS transistor switches on, C delivers a negative voltage through the series diode to the output. The zener serves as a dissipative regulator.

Positive input Negative output Charge pump Circuit Diagram

 Positive input Negative output Charge pump Circuit Diagram

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Simple Photomultiplier Supply Circuit Diagram

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This is a Simple Photomultiplier Supply Circuit Diagram and Cockcroft-Walton voltage multiplier supplies the stepped voltage required for the dynodes of the PMT without the power-wasting voltage- divider resistor string that is traditionally used.

Simple Photomultiplier Supply Circuit Diagram


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Build a Regulated driven Converter Circuit Diagram

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How to Build a Regulated driven Converter Circuit Diagram?.This converter delivers up to 50 mA from a 6-V battery with 78% efficiency. This flyback converter functions by feedback-controlling the frequency of inductive flyback events. The inductor`s output, rectified and filtered to de, biases the feedback loop to establish a stable output. If the converter`s output is below the loop setpoint, A2`s inputs unbalance and current is fed through the 1-MO resistor at Al. This ramps the 1000-pF value positive. When this ramp exceeds the 0.5-V potential at A1 `s positive input, the amplifier switches high. 

 Regulated driven Converter Circuit Diagram

Regulated driven Converter Circuit Diagram


Q2 turns on, discharging the capacitor to ground. Simultaneously, regenerative feedback through the 200-pF value causes a positive-going pulse at A1`s positive input, sustainlljg A1`s positive output. Q1 comes on, allowing inductor, 11, current to flow. When A1`s feedback pulse decays, its output becomes low, turning off Ql. Q1`s collector is pulled high by the inductor`s flyback and the energy is stored in the 100-I`F capacitor. The capacitor`s voltage, which is the circuit output, is sampled by A2 to close a loop around Al/Ql. This loop forces A1 to oscillate at whatever frequency is required to maintain the 15-V output. 

In-phase transformer windings for the drain and gate of TMOS power FET Q1 cause the circuit to oscillate. Oscillation starts when the feedback coupling capacitor, C1, is charged from the supply line via a large resistance; R2 and R3 limit the collector current to Q2. During pump-up, the on time is terminated by Q2, which senses the ramped source current of Ql. C1 is charged on alternate half-cycles by Q2 and forward-biased by zener D2. 

When the regulated level is reached, forward bias is applied to Q2, terminating the on time earlier at a lower peak current. When this occurs, the frequency increases in inverse proportion to current, but the energy per cycle decreases in proportion to current squared. Therefore, the total power coupled through the transformer to the secondary is decreased.
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Simple Dual 50V/5A Universal Power Supply Circuit Diagram

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This is the simple Dual 50V/5A Universal Power Supply Circuit Diagram. Tl has two primaries and six secondaries; the two 120-VAC primaries and 6.3-VAC secondaries are in parallel. Modules A and are identical; hence, only Module A`s parts are called out. Module C is wired point-to-point on the IC3 heat-sink.

Dual 50V/5A Universal Power Supply Circuit Diagram

Dual 50V/5A Universal Power Supply Circuit Diagram

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Simple Positive Regulator Circuit Diagram

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In the Simple Positive Regulator Circuit Diagram, Ql and Q2 are connected in the classic SCR or thyristor configuration. Where higher input voltages or minimum component count are required, the circuit for thyristor boost can be used. 

  Positive Regulator Circuit Diagram

 Positive Regulator Circuit Diagram


The thyristor is running in a linear mode with its cathode as the control terminal and its gate as the output terminal. This is known as the remote base configuration.
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Top Bench Power supply Circuit Diagram

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This is the Top Bench Power supply Circuit Diagram. A tapped transformer drives a diode bridge (D1-D4) and two 2500 µ¥ filter capacitors (Cl and C2), that provide a no-load voltage of 37 or 47 volts, depending upon the position of switch S2a. The unregulated dc is then fed to a pre-regulator stage composed of Ql and D5. 

Those components protect IC1 (the 723) from an over-voltage condition; the 723 can't handle more than 40 volts. The LED (LED1) and its 2.2 k current-limiting resistor (Rl) provide on/off indication. The current through the LED varies slightly according to the transformer tap selected, but that's of no real consequence.

 Top Bench Power supply Circuit Diagram

 Top Bench Power supply Circuit Diagram

 The series-pass transistor in IC1 drives voltage-follower Q2, providing current amplification. The transistor can handle lots of power. It has a maximum collector current of 15 amps and a maximum VCE of 70 V, both of which are more than adequate for our supply.
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Simple Fixed-Current Regulator Circuit Diagram

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This Simple Fixed-Current Regulator Circuit Diagram 1-mA current source delivers a fixed current to a load connected between Ql`s collector and ground; the load can be anywhere in the range from 0 to 14 . The circuit is powered from a regulated 15-V supply, and the R1/R2 voltage divider applies a 14-V reference to R3. 

The op amp`s output automatically adjusts to provide an identical voltage at the junction of R4 and R5. That produces 1 V across R5, resulting in an R5 current of 1 mA. Because that current is derived from Ql`s emitter, and the emitter and collector currents of a transistor are almost identical, the circuit provides a fixed-current source. The output current can be doubled by halving the value of R5.

Fixed-Current Regulator Circuit Diagram

Simple Fixed-Current Regulator Circuit Diagram

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Over voltage Protection Circuit Diagram

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This is a Over voltage Protection Circuit Diagram. A silicon-controlled rectifier is installed in parallel with the 12-V line and connected to a normally-closed 12-V relay, K1. The SCR's gate circuit is used to sample the applied voltage. As long as the applied voltage stays below a given value, SCR1 remains off and Kl's contacts remain closed, thereby supplying power to the load. 

When the source voltage rises above 12 V, sufficient current is applied to the gate of SCR1 to trigger it into conduction. The trigger point of SCR1 is dependent on the setting of R1. Once SCR1 is triggered (activating the relay), K1's contacts open, halting current flow to the load.

Over voltage Protection Circuit Diagram

Over voltage Protection Circuit Diagram

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Build a Bridge balance indicator Circuit Diagram

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How to Build a Bridge balance indicator Circuit Diagram. This Indicator circuit provides an accurate comparison of two voltages by indicating their degree of balance (or imbalance). Detecting small variations near the null point is difficult with the basic Wheatstone bridge alone. Amplification of voltage differences near the null point will improve circuit accuracy and ease of use. The 1N914 diodes in the feedback loop result in high sensitivity near the point of balance (R1/R2 = R3/R4). 

When the bridge is unbalanced the amplifier's closed-loop gain is approximately Rp/r, where r is the parallel equivalent of Rl and R3. The resulting gain equation is G = RF(1/R1 + 1/R3). During an unbalanced condition the voltage at point A is different from that at point B.

This difference voltage (V^), amplified by the gain factor G, appears as an output voltage, As the bridge approaches a balanced condition (R1/R2 = R3/R4), V^ approaches zero. As V^ approaches zero the 1N914 diodes in the feedback loop lose their forward bias and their resistance increases, causing the total feedback resistance to increase. This increases circuit gain and accuracy in detecting a balanced condition. The figure shows the effect of approaching balance on circuit gain. The visual indicator used at the output of the OP-07 could be a sensitive voltmeter or oscilloscope.

Bridge balance indicator Circuit Diagram

Bridge balance indicator Circuit Diagram

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Simple Bridge Rectifier Circuit Diagram

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This Simple Bridge Rectifier Circuit Diagram is intended for those cases where two unequal supply voltages are required. The lower voltage is obtained with the aid of a transformer with symmetric windings and half-wave rectification of the potential across one winding. For the higher voltage, the potential across both windings is rectified. To that end, the output of the transformer is linked to the bridge rectifier via two electrolytic capacitors that provide isolation of the two direct voltages. 

 Simple Bridge Rectifier Circuit Diagram


 Simple Bridge Rectifier Circuit Diagram

A bonus with this type of circuit is that although the two supplies can be loaded unequally, the currents through the two transformer windings are the same. Thus, the transformer is loaded symmetrically so that its full capacity can be used. Moreover, no unnecessary dissipation is in the voltage regulators. The load on the lower voltage supply depends primarily on the rating of the transformer. The load on the higher voltage supply is limited by the reactance of Cj and C2 (= xh r 50 C) and the required minimum output voltage.
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Build a Regulated Charge Pump Circuit Diagram

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How to Build a Regulated Charge Pump Circuit Diagram. The dc-dc converter substitutes a voltage triplet in place of the external inductor and the diode that`s typically associated with the switching regulator, IC1. Inverting and non inverting amplifiers in the MOS-FET-driver (IC2) activate a diode-capacitor tripling network (D1 through D3, CI through C3). 

A 50-kHz oscillator residing within IC1 produces the EXT signal (pin 6), IC2 converts this signal into drive signals (180° out of phase) for the tripler. The resulting charge-discharge action in the capacitors recharges C3 toward 10 V every 20 The ferrite bead limits output ripple to about 20-mVpp for a 50-mA load. Conversion efficiency is about 70% for the 5-V input, 10-V output configuration.


Regulated Charge Pump Circuit Diagram

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Simple Voltage controlled current source with grounded source and load

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This is a Simple Voltage controlled current source with grounded source and load. This is a simple, precise voltage-controlled current source. Bipolar supplies will permit bipolar output. Configurations featuring a grounded voltage- control source and a grounded load are usually more complex and depend upon several components for stability.Voltage-controlled-current-source-with-grounded-source-and-load. In this circuit, accuracy and stability almost entirely depend upon the 100-0 shunt.

Voltage controlled current source circuit diagram

Simple Voltage controlled current source with grounded source and load


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Simple Positive And Negative Voltage Power Supply Circuit Diagram

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This Simple Positive And Negative Voltage Power Supply Circuit Diagram provides a precision voltage source that can be adjusted through zero to positive and negative voltages, which eliminates reversing connections on the power supply. Also, it is possible to get exactly 0 V, without some offset. As to how this circuit works, first consider the -1 V/V to +1 V/V linear gain-control amp (see the figure). A Burr-Brown INA105 difference amp is used in a unity-gain inverting amp configuration. 

 Positive And Negative Voltage Power Supply Circuit Diagram

Simple Positive And Negative Voltage Power Supply Circuit Diagram


A potentiometer is connected between the input and ground. The pot`s slider is connected to the noninverting input of the unity-gain amp; this input is typically connected to ground. With the slider at the bottom of the pot, the circuit is a normal-precision unity-gain inverting amp with a gain of -1.0 V/V ± 0.01% maximum. 

With the slider at the top of the pot, the circuit is a normal-precision voltage follower with a gain of ± 1.0 V/V ± 0.001% maximum. With the slider in the center, there`s equal positive and negative gain for a net gain of 0 V/V. The accuracy between the top and the bottom will usually be limited by the accuracy of the pot.

Source Simple Positive And Negative Voltage Power Supply Circuit Diagram
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Simple Power Converter Circuit Diagram

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This simlpe Power Converter Circuit Diagram consists of an a stable multivibrator driving a push-pull pair of transistors into the transformer primary. The multivibrator frequency should~equal around 1 or 2kHz. For higher de voltages, voltage multipliers on the secondary circuit have been used successfully to generate 10 k V from a 40~stage multiplier like the one shown.

Power Converter Circuit Diagram

Power Converter Circuit Diagram

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Build a High Voltage Inverter Circuit Diagram

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The High Voltage Inverter Circuit Diagram converts a de voltage (V +) to a high-amplitude square wave in the audio-frequency range. The dual timer, IC2, provides an inexpensive alternative to the traditional transformer for providing complementary base drive to the power transistors, Ql and Q2. You can convert a 6 to 12 V battery output, for example, to an ac amplitude, which is limited primarily by the power rating of transformer Tl. 

Connect timer IC1 as an oscillator to provide a symmetrical square-wave drive to both inputs of IC2. The timing components, R2 and Cl, produce a 2.2-kHz output frequency. By connecting half of IC2 in the inverting mode and the other half in noninverting mode, the timer`s outputs alternately drive the two transistors. 

 Build a High Voltage Inverter Circuit Diagram


Build a High Voltage Inverter Circuit Diagram

You can operate the audio-output transformer, Tl, as a step-up transformer by connecting it backwards using the output winding as an input. The transformer delivers an output voltage across RL of 4 x N x V+V pk-pk, where Nis the transformer turns ratio. For the circuit shown, the output swing is 100 x V+V pk-pk.
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Twin Audio Amplifier Power Supply Circuit Diagram

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A Twin Audio Amplifier Power Supply Circuit Diagram that will deliver 50 W per channel is shown in the schematic. It includes preamp and tone controls, and also includes a headphone amplifier. The circuit depicts the power supply that supplies 38.5 V and 15 V regulated for the dual 50 watt.

Twin Audio Amplifier Power Supply Circuit Diagram

Twin Audio Amplifier Power Supply Circuit Diagram

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Medium Power Inverter Circuit Diagram

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In this Medium Power Inverter Circuit Diagram, a CMOS inverter, such as the CD4069, is used to convert the open drain Lx output to a signal suitable for driving the gate of an external P MOSFET. The MTP8P03 has a gate threshold voltage of 2.0 V to 4.5 V, so it will have a relatively high resistance if driven with only 5 V of gate drive. 

To increase the gate drive voltage, and thereby increase efficiency and power handling capability, the negative supply pin of the CMOS inverter is connected to the negative output, rather than to ground. Once the circuit is started, the P MOSFET gate drive swings from +5 V to -Vour· At start up, the -Vour is one Schottky diode drop above ground and the gate drive to the power MOSFET is slightly less than 5 V. 

Medium Power Inverter Circuit Diagram

Medium Power Inverter Circuit Diagram
 

The output should be only lightly loaded to ensure start up, since the output power capability of the circuit is very low until -VoUT is a couple of vults. This circuit generates complementary output signals from 50 to 240 Hz. Digital timing control ensures a separation oflO to 15° between the fall time of one output and the rise time of the complementary output. The digital portion of inverter Ul to U4 controls the drive to Q1 and Q2, both MTE60N20 TMOS devices. 

These devices are turned on alternately with 11.25° separation between complementary outputs. A +12-V supply for CMOS gates U1 to U4 is developed by T1, D3, D4, C7, and U6. The power supply for the TMOS frequency generator is derived from the diode bridge, U5, and capacitor C7; it is applied to the center tap of T2.
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Simple 3V Power Supply Circuit Diagram For Portable Radios

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This is the Simple 3V Power Supply Circuit Diagram For Portable Radios. Most small portable radios require a 3-V supply, which is normally provided by two AA or AAA batteries .Because rechargeable batteries are an option with many of these radios, most of them are fitted with a charger socket. When such radios are used in a stationary condition (e.g., in the kitchen or in the office), it is useful (and economical) to use the mains-operated supply described here. 

The supply is small enough to be fitted inside the radio or in a mains adapter case (less than transformer). Voltage regulator IC1 is adjusted for an output of 3 V by resistors RI and R2, which are decoupled by C2. Capacitor C3 provides additional filtering. Diode D1 indicates whether the unit has been connected to the mains. The diode also provides the load necessary for the regulator to function properly; in its absence, the secondary voltage of the transformer might become too high when the unit is not loaded. 

The transformer should be a short-circuit-proof miniature type, which is rated at 12 V and 4.5 VA. The secondary voltage is slightly higher than needed for a radio, but this reserve is useful when the unit is used with a cassette or CD player. It is advisable to check the output voltage of the unit when it is switched on for the first time before connecting it to a radio or cassette player. 

 3V Power Supply Circuit Diagram For Portable Radios

3V Power Supply Circuit Diagram For Portable Radios

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Build a Isolated 15V To 2500V Power Supply Circuit Diagram

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Build a Isolated 15V To 2500V Power Supply Circuit Diagram. A dc-dc converter using a 74HC04 drives Tl. Tl is a ferrite-core transformer using a Fair-Rite, Inc. P/N 5975000201 (uo + 5000) and has a 7-turn primary and a 25-turn secondary. Kynar, #30 wirewrap wire is used. With Tl, the circuit isolation is good to 2500 V.

Isolated 15V To 2500V Power Supply Circuit Diagram

Isolated 15V To 2500V Power Supply Circuit Diagram

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Simple Wind battery Charger Circuit Diagram

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This is a Simple Wind battery Charger Circuit Diagram. The dc motor is used as a generator with the voltage output being proportional to its rpm. The LTC1042 monitors the voltage output and provides the following control functions. If generator voltage output is below 13.8 V, the control circuit is active and the Ni-Cad battery is charging through the LM334 current source. The lead acid battery is not being charged. 

If the generator voltage output is between 13.8 V and 15.1 V, the 12 V lead acid battery is being charged at about 1 amp/hour rate (limited by the power FET). If generator voltage exceeds 15.1 V (a condition caused by excessive wind speed or 12 V battery being fully charged) then a fixed load is connected limiting the generator rpm to prevent damage. This charger can be used as a remote source of power where wind energy is plentiful such as on sailboats or remote radio repeater sites. Unlike solar powered panels, this system will function in bad weather and at night.

Simple Wind battery Charger Circuit Diagram

Simple Wind battery Charger Circuit Diagram

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Build a 200Ma-12v ni-cad Battery Charger Circuit Diagram

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This 200Ma-12v ni-cad Battery Charger Circuit Diagram charges the battery at 75 mA battery can be left in the charger indefinitely, until the battery is charged, then it reduces the To set the shut-off point, connect a 270-ohm, current to a trickle rate

It will completely 2-watt resistor across the charge terminals and recharge a dead battery in four hours and the adjust the pot for 15 volts across the resistor. 

 200Ma-12v ni-cad Battery Charger Circuit Diagram


200Ma-12v ni-cad Battery Charger Circuit Diagram
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Simple Microprocessor power supply watchdog circuit Diagram

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The Simple Microprocessor power supply watchdog circuit Diagram monitors the input to the microprocessor 5 V regulated supply for voltage drops and initiates a reset sequence before supply regulation is lost. In operation, the resistor capacitor combination Rs and Cj form a short time constant smoothing network for the output of the fullwave bridge rectifier. 

An approximately triangular, voltage waveform appears across C and Rs and it is the minimum excursion of this that initiates the reset. Diode Dg prevents charge sharing between capacitors Cj and Ck. Resistors Rn and Rm form a feedback network around the voltage reference section of the LM10C, setting a threshold voltage of 3.4 volts. 

 Microprocessor power supply watchdog circuit Diagram

Simple Microprocessor power supply watchdog circuit Diagram


The threshold voltage is set at 90% of the minimum voltage of the triangular waveform. When the triangular wave trough, at the comparators non-inverting input, dips below the threshold, the comparator output is driven low. This presents a reset to the microprocessor. Capacitor Ch is charged slowly through resistor Rk and discharged rapidly through diode De.
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Safe Constant Current Source Circuit Diagram

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In the Safe Constant Current Source Circuit Diagram shown, a CMOS op amp controls the current through a p-channel HEXFET power transistor to maintain a constant voltage across RL The current is given by: 1 ~ VREF/Rl. The advantages of this configuration are: (a) in the event of a component failure, the load current is limited by Rl; and (b) the overhead voltage needed by the op amp and the HEXFET is extremely low.


Safe Constant Current Source Circuit Diagram

Safe Constant Current Source Circuit Diagram

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Build a Heavy Duty Battery Charger Circuit Diagram

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How to Build a Heavy Duty Battery Charger Circuit Diagram. Operation amplifier A1 directly drives the VN64GA with the error signal to control the output voltage. Peak rectifier Dl, CI supplies error amplifier A1 and the reference zener. This extra drive voltage must exceed its source voltage by several volts for the VN64GA to pass full load current. 

The output voltage is pulsating dc which is quite satisfactory for battery charging. To convert the system to a regulated dc supply, capacitor C2 is increased and another electrolytic capacitor is added across the load. The response time is very fast, being determined by the op-amp. 

 Heavy Duty Battery Charger Circuit Diagram

Heavy Duty Battery Charger Circuit Diagram


The 2N4400 current limiter circuit prevents the output current from exceeding 4.5 A. However, maintaining a shorted condition for more than a second will cause the VN64GA to exceed its temperature ratings. A generous heat sink, on the order of 1°C/W, must be used.
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Very Low Dropout Linear Regulator Circuit Diagram

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This linear post regulator provides 12 V at 3 A. It employs TL431 reference Ul which, without additional amplification, drives TMOS MTP3055A gate Ql series pass regulator. Bias voltage is applied through Rl to Q1`s gate, which is protected against overvoltage by diode CRl. 

Frequency compensation for closed-loop stability is provided by Cl. Key performance features are: Dropout voltage: 0.6 V Load regulation: lOmV Line regulation: ± 5 m V Output ripple: 10 mVpk-pk

Low Dropout Linear Regulator Circuit Diagram

Low Dropout Linear Regulator Circuit Diagram

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Basic DC to DC Converter Electronic Schematic Diagram

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Those of you who frequently use devices that work on battery or you need a negative trend at the moment you have a single positive, will definitely look for a converter like the one described below. Constructing it, you can convert a positive voltage of a battery of 9 V to negative using well known integrated 555. The same circuit can also be used in cases those requiring two symmetrical lines of power, when available a single battery. 

The integrated TLC555 is the old bipolar NE555, manufactured with technology but CMOS. Unless you have this type of integrated, you might as well use an 7555. In this construction, the TLC555 is syndesmologimeno arranged in a ground unstable.The oscillation frequency determined by the A2, A3, C 1 and approaching 20 kHz. 

 DC to DC Converter Electronic Schematic Diagram

DC to DC Converter Electronic Schematic Diagram


The rectangular waveform produced by the oscillator is therefore time to time (Duty Cycle) close to 50%. The waveform is led to a rectifier Doubler formed by C3, O1, O2 and C4. In place of O1 and O2 should be placed diodes Schottky type VAT85 due to low voltage correct direction which is equal to 0,4 V (silicon diodes such as type 1 N4148, show a tendency equal to 0,7 V). The capacitor C4 cares for smoothing the voltage bristled, while the C5 relieve the signal from noise high frequencies. With the help of A1, C6 and C7 achieved the disconnection of supply voltage timer. 

The consumption of the inverter to power depends largely on the load to be connected to the output of -9 V. As seen from the values ??indicated in the table, the output voltage is held within tolerable levels, as the load current is kept less than 1O mA. To make it easy to integrate the inverter into any electronic device, I suggest you build a small PCB board.
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Simple Inductance Bridge Circuit Diagram

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This Inductance Bridge Circuit Diagram will measure inductances from about 1 to 30 at a test frequency of 5 mHz. A 365-pF AM-type tuning capacitor is used as a variable element. The circuit should be constructed in a metal enclosure. Calibration can be done on known inductors or by plotting a curve of the capacitance of the 365-pF capacitor versus rotation and calculating the inductance from this. 

The range of measurement can be charged by using a different frequency crystal and/or variation of L2 and C6.

Inductance Bridge Circuit Diagram

Simple Inductance Bridge Circuit Diagram

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Coming Soon: The Slicker, Faster and – Maybe – Cheaper iPhone

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Excitement over the new iPhone is building to a frenzy this week as rumors abound that Apple (AAPL) will unveil upgraded models on September 10.
That would be almost exactly a year after Apple introduced the iPhone 5, which grabbed the title of best selling smart phone model in the world last year.
Apple isn’t commenting on new models yet but the September 10 introduction date has been confirmed by major news organizations including the Wall Street Journal’s AllThingsD and dedicated Apple bloggers such as Jim Dalrymple.
The rumored new handset, expected to be called the iPhone 5S, will probably look quite similar to the current model 5 but is sure to be lighter and more powerful than ever. It may also be accompanied by a lower-priced, plastic-cased model, dubbed the iPhone “5C” on the Internet.
iPhone 5C
Pictures leaked onto the Web of the purported lower-priced iPhone show an array of bright colors instead of just the same old black and white models available in recent years. That would make 2013 a banner year for colorful phones, as the new Google (GOOG) Moto X phone arriving in stores in a few weeks is being offered in 18 colors.
A rising share price
And it's not just customers who are excited about a new iPhone. Investors have been driving up Apple's share price — even before billionaire hedge fund manager Carl Icahn tweeted this week that he had bought a large position. After lagging the market for most of the year, Apple shares have gained 17% over the past month.
Apple remains a top player at the high end of the smartphone market, especially in the United States, where most carriers subsidize more than two-thirds of the cost of a new phone for customers who sign a two-year contract.
The lower-priced phone would help Apple better compete for customers who pay month to month and those who live in less-wealthy countries where carriers don’t offer subsidies. Apple currently offers older models, such as the 2010 iPhone 4, to those customers. But the older phone still costs $450 without a subsidy and may lack the appeal of more recent models running Google’s Android software.
“They’ve been wickedly profitable but their market share is kind of plateauing,” says Ramon Llamas, mobile research manager at IDC. Apple captured 18% of the smartphone market in 2011 and 2012, according to IDC. “A little more attention to emerging markets is warranted.”
Competitors with $200 to $300 phones have been growing faster than Apple in many less-wealthy markets, according to data from Gartner. Apple sold 31.9 million phones worldwide in the second quarter, up just 10% from a year earlier, Gartner reported, second to Samsung. But Apple’s next three competitors – LG Electronics (066570.KS), Lenovo Group (0992.HK) and ZTE (0763.HK) – sold almost as many, 31.8 million combined, as their sales jumped 93%.
Still, Llamas isn’t sure a new lower-priced phone is needed. Lower pricing and greater promotions of older models could work just as well, he argues.
Could the cheap phone move backfire?
And Apple’s rumored move to offer lower-priced new iPhones could backfire. Some analysts fear that a portion of wealthy customers will forgo buying more-expensive models in favor of the “5C.” That could cut into Apple’s revenue and profits. The move could also tarnish Apple’s reputation as a leading premium phone maker, particularly if the lower-priced model is seen as chintzy or with key functions crippled.
But if Apple announces a lower-priced model, it is more likely to create a desirable, full-featured product in keeping with the company’s premium image, according to John Gruber, who has followed Apple for over a decade at his website, DaringFireball.net.
“The 5C is not about selling a piece of junk to some sort of unwashed masses,” Gruber wrote on Tuesday. “It’s about continuing to push the price down to expand the iPhone’s market without changing what the iPhone brand stands for.”
At the high end
Following a pattern Apple has established over several years, the new high-end iPhone is likely to retain the outward appearance of the current iPhone 5. Apple tends to produce a major iPhone overhaul only every other year, in keeping with the two-year contract cycle of many mobile phone subscribers. And pictures floating on the Internet show a rumored new iPhone with a similar shape and upgraded internal components to the current model.
iPhone 5S camera
But many analysts expect Apple may incorporate a brand-new feature this year – a fingerprint reader hidden in the iPhone’s tiny home button. Apple bought mobile security firm AuthenTec and its fingerprint-scanning technology last year for $356 million. And text contained in beta versions of Apple’s new iOS 7 software appears to reference a finger print sensor, too.
“It’s a great way to ease the hassle of remembering passwords,” says Ken Hyers, senior analyst at Strategy Analytics. “It will be much more reliable than the facial-recognition technology that Samsung first introduced with the Galaxy S3, and easier to use, too.”
Combined with several wireless technologies already in the iPhone, the fingerprint scanner could also be part of a new mobile-payments network from Apple. That would be quite different from Google’s Google Wallet payment system, which relies on phones that have specialized hardware, known as a Near Field Communications, or NFC, chip. U.S. mobile carriers have blocked Google Wallet apps and are planning to roll out their own NFC-based payment network known as Isis. But neither has caught on yet.
Apple’s system, relying on Bluetooth and Wifi standards, could ignore the NFC wars and build off its existing iOS app called Passbook, which currently works for items like travel and entertainment tickets. Apple mobile development chief Craig Federighi made fun of Android's NFC-based file transfer system at the company's developer conference in June. "There's no need to wander around the room bumping your phone," he said, referencing the system featured prominently in Samsung television ads.
Apple fans hoping for a bigger screen are likely to be disappointed. Android phones have featured ever larger screens – the new LG G2 model unveiled August 7 has a 5.2” screen, one of the biggest yet. Google's Moto X phone has a 4.7" screen.
But Apple is trying to avoid further fragmenting its lineup in order to make it easier for developers to write apps that will look good and run smoothly on all iOS hardware. Analysts expect Apple will stick with the 4” screen introduced on last year's iPhone 5. The screen was slightly longer than earlier models but maintained the same width, so apps that weren’t updated for the new size could just display a black bar over the extra space.
Some analysts say Apple needs to move to bigger screens to better compete against Android. That probably won't happen until the company's 2014 upgrade cycle.
“It’s just like in the movie 'Jaws' – what we need is a bigger boat,” says Roger Entner, founder of Recon Analytics. “If you’re going to charge a premium and seek to delight your customers, you have to be leading, not following, the trend.”

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Current Limiting Coil Driver circuit Diagram

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This is the Practical Current Limiting Coil Driver circuit Diagram. The p-channel devices are switched off by current sensors when the coil current reaches 10 A. The operation is similar to that of a switching-type power supply. The Schottky diodes and resistors are for spike protection.

Current Limiting Coil Driver circuit Diagram

Current Limiting Coil Driver circuit Diagram

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Zener Diode Increase Regulator Output Circuit Diagram

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A zener diode in the ground lead of a fixed pnp regulator varies the voltage output of that device without a significant sacrifice in regulation. The technique also allows the regulator to operate with output voltages beyond its rated limit.

Zener Diode Increase Regulator Output Circuit Diagram

Zener Diode Increase Regulator Output Circuit Diagram

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Preregulator for Power Supply Circuit Diagram

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This SCR pre-regulator keeps the filter capacitor Vc, in a variable output power supply, a few volts above the output voltage V0. The benefits include: less heat dissipated by the pass transistor and therefore small heatsink, cooler operation and higher efficiency, especially at low output voltages. Ql, Rl, R2, Dl and D2 form a constant current source for zener Zl, so that the contribution to the output current is always a few mA (2-3 mA). The Darlington pair Q2, Q3 keeps the SCR off.

Preregulator for Power Supply Circuit Diagram

Preregulator for Power Supply Circuit Diagram


The voltage Vc decreases until Vc = V0 = V at which point the Darlington pair fires the SCR, charging the filter capacitor to a higher voltage VC1 in less than half the period of the input voltage. The component values, shown are for a 0 - 250-V, 3-A power supply.


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USB 3.0 Types

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Three transistor audio amplifier

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Switching inverter for 12v systems circuit diagram

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This PWM control circuit provides the control pulse to the DMOS Power Switch in the flyback circuit. The output of the PWM is a pulse whose width is proportional to the input control voltage and whose repetition rate is determined by an external clock signal. 

To provide the control input to the PWM and to prevent the output voltage from soaring or sagging as the load changes the error amplifier and reference voltage complete the design. They act as the feedback loop in this control circuit much like that of a servo control system.


Switching inverter for 12v systems circuit diagram

Switching inverter for 12v systems circuit diagram

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Build a 5V Supply Circuit Diagram

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This 5V Supply Circuit Diagram protects microprocessor systems from `brownouts` without the expense of an uninterpretable power supply. Designed around a small 9-V nickel cadmium battery the circuit continues to provide a constant 5-V output during brownouts of up to a few seconds. Load currents of up to 500 mA may be drawn using the components shown. 

With this mains-derived supply present, D5 is forward biased so that the stabilized supply powers the 5-V regulator and hence the circuitry to be protected. FET Tj is held on by Dl, its drain current being provided from the dc supply via Rb and D2. Diode D3 is reverse-biased so that T2 is off, and the battery is isolated from D6. RCH and D4 serve to trickle charge the battery with approximately 1.2 mA. 

 5V Supply Circuit Diagram

5V Supply Circuit Diagram


When the 12-V supply is removed, Rl and Cl initially keep Tl switched on. D3 is now forward biased, so that Tl drain current is drawn via Rb, D3 and T2 from the battery. This switches T2 on, allowing the load circuitry to draw current from the battery via D6 and the 5-V regulator. After a few seconds Cl has discharged (via Rl) such that Vgs falls below the threshold value for the FET, and Tl switches off. There is then no path for T2 base current, so that it also switches off, isolating the battery.
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