There are 164 circuit schematics available in this category. Click here for all circuit diagrams. The Last circuit was added on Saturday, January 28, 2023.Please note some adblockers will suppress the schematics as well as the advertisement so please disable if the schematic list is empty.

Filter schematics by description:

CircuitCategoryDate AddedOK?Votes 
13.8V 30-40A Power Supply (PDF)Power Status86 vote up vote down
Car Ignition Coil Driver from 110V ACPowerSep 23, 2024Status-10 vote up vote down
Amplified zener regulatorPower Status-4 vote up vote down
Car Ignition Coil Driver from 12V DC - Can be used as an electric fencePowerSep 23, 2024Status3 vote up vote down
Battery Charger, Current and Voltage Regulated for Sealed Lead Acid batteriesPower Status-7 vote up vote down
Voltage and current regulated power supplyPowerSep 23, 2024Status-3 vote up vote down
Simple switching power supply (mains operated)PowerSep 23, 2024Status3 vote up vote down
12 Volt Switching Power Supply circuit diagram and PCB layoutPowerSep 23, 2024Status-6 vote up vote down
Simple voltage booster based on Linear Technologies LT1372, includes PCB designPowerSep 23, 2024Status-1 vote up vote down
Alkaline battery chargerPowerDec 02, 2024Status0 vote up vote down
Highly accurate constant current source using LM4140, OP777 and MOSFETPowerMar 17, 2024Status-2 vote up vote down
Dry cell battery chargerPowerDec 07, 2024Status4 vote up vote down
Power Supply Resumption Alarm using 555 timerPowerOct 25, 2024Status-4 vote up vote down
Solid-state voltage indicator with high voltage cutoutPowerDec 07, 2024Status0 vote up vote down
Stabilized Power Supply With Short-Circuit IndicationPowerOct 25, 2024Status-1 vote up vote down
Capacitor voltage stepper using 555 timerPowerDec 07, 2024Status-2 vote up vote down
Low Voltage Alarm for batteries and other volatile DC power sourcesPowerJun 26, 2024Status-3 vote up vote down
Voltage Monitor using UA741 operational amplifierPowerOct 19, 2024Status-3 vote up vote down
Expanded Scale Battery Volt MeterPowerSep 17, 2024Status0 vote up vote down
Battery Low Voltage BeeperPowerSep 17, 2024Status-1 vote up vote down
Low Cost Universal Battery ChargerPowerJan 08, 2025Status-2 vote up vote down
26V-to-5000V DC-DC ConverterPowerJan 08, 2025Status-2 vote up vote down
Fast Charger for Better Lead-Acid Battery LifePowerOct 03, 2024Status0 vote up vote down
5 A Constant Voltage-Constant Current RegulatorPowerOct 03, 2024Status-1 vote up vote down
1A Variable Regulated Power SupplyPower Status-1 vote up vote down
Regulated Power Supply CircuitsPowerSep 10, 2024Status0 vote up vote down
Basic Solid State RelaysPowerSep 10, 2024Status-3 vote up vote down
LM311 Thermostat circuit diagramsPower Status-1 vote up vote down
Transformer Secondary Voltage ReductionPower Status1 vote up vote down
Back And Forth - Bidirectional Bipolar Stepper Motor DriverPower Status1 vote up vote down
High Side Current Monitors (LM358, Zetex - ZXCT-1009)PowerSep 10, 2024Status0 vote up vote down
Low Battery Voltage Cutout CircuitsPowerSep 10, 2024Status-2 vote up vote down
Preselect Twin Coil Switch Machine CircuitPower Status-3 vote up vote down
N.O. Magnetic Reed Switch ON /OFF Circuit (SCR equivalent)Power Status-2 vote up vote down
Team digital - SCR16 - Twin Coil Switch Machine AdapterPower Status-1 vote up vote down
Efficient unipolar stepper motor driver (only uses power when it makes a step)Power Status0 vote up vote down
Alternative power source for Magellan GPS receiversPowerMay 01, 2024Status0 vote up vote down
Battery voltage monitor using an LM358 op-ampPowerApr 12, 2024Status-1 vote up vote down
0-14 volt, 0-2 amp current limited variable power supply regulatorPower Status-2 vote up vote down
A Variable power supply with adjustable current limiting. 0-14V output up to 5A current.PowerApr 12, 2024Status0 vote up vote down
Dynamo Current and Voltage RegulatorPowerSep 21, 2024Status-2 vote up vote down
General purpose portable DC power supply using rechargeable C cellsPowerFeb 05, 2025Status-2 vote up vote down
Bench power supply that allows a number of varying output voltages to be preset. Includes PCB layoutPowerFeb 26, 2025Status-2 vote up vote down
Power supply metering circuits for measuring both voltage and currentPowerFeb 09, 2025Status-5 vote up vote down
Emergency power systemPowerMay 16, 2024Status-3 vote up vote down
Digital bench power supply based on a PIC16F870PowerMay 24, 2024Status-2 vote up vote down
Lithium Ion Battery Charger based on a PIC micro including circuit diagram and source codePowerMay 24, 2024Status0 vote up vote down
6V to 12V ConverterPower Status-2 vote up vote down
Automatic 12V Lead Acid Battery ChargerPowerSep 01, 2024Status0 vote up vote down
Solid State Tesla Coil/High Voltage GeneratorPowerSep 01, 2024Status-1 vote up vote down
12V to 120V Inverter circuit diagramPowerSep 01, 2024Status-4 vote up vote down
Basic Power SupplyPowerSep 01, 2024Status2 vote up vote down
High Current Power SupplyPowerSep 01, 2024Status-1 vote up vote down
Dual Polarity Power SupplyPowerSep 01, 2024Status-1 vote up vote down
High Voltage High Current Power SupplyPowerSep 01, 2024Status-3 vote up vote down
Transformerless Power SupplyPowerSep 01, 2024Status-5 vote up vote down
Fixed Voltage Power SupplyPowerSep 01, 2024Status-1 vote up vote down
Voltage Inverter using 555 TimerPowerSep 01, 2024Status-2 vote up vote down
Voltage Inverter using LM380 audio amplifier ICPowerSep 01, 2024Status-3 vote up vote down
Dual power supplyPowerJan 31, 2025Status-1 vote up vote down
Negative voltage generatorPowerAug 12, 2024Status1 vote up vote down
Power reminder beeper (PDF)PowerJan 26, 2025Status-1 vote up vote down
Unplugged power cord alarmPowerJan 26, 2025Status-1 vote up vote down
Machine power loss beepter (PDF)PowerJan 26, 2025Status-1 vote up vote down
Op-Amp Current Source with Floating Load including SPICE simulationPowerMar 26, 2024Status-1 vote up vote down
Dual Polarity Unregulated PSU For High-End Audio AmpsPowerNov 13, 2024Status-1 vote up vote down
High Voltage Converter: 90V From 1.5VPowerNov 13, 2024Status-1 vote up vote down
Charge Monitor for 12V lead acid batteryPower Status0 vote up vote down
NiCd Cell ChargerPower Status-2 vote up vote down
Basic UPS Power SupplyPowerFeb 21, 2025Status0 vote up vote down
Fuse monitor / alarmPowerFeb 21, 2025Status-1 vote up vote down
Voltage monitor with LED indicatorPowerFeb 21, 2025Status-2 vote up vote down
High current regulated power supplyPowerOct 31, 2024Status-1 vote up vote down
Adjustable power supply using LM317PowerJan 26, 2025Status-2 vote up vote down
Simple +5V power supply circuitPowerJan 26, 2025Status-1 vote up vote down
Basic 78xx series regulator mains power supply circuit diagramPowerOct 25, 2024Status-2 vote up vote down
USB charger circuit diagramPowerAug 18, 2024Status0 vote up vote down
Advanced High Voltage PSU circuitPower Status-1 vote up vote down
12 Vdc - 120 Vac Inverter SchematicPowerJan 01, 2025Status-2 vote up vote down
Single to 3-phase power conversionPower Status-1 vote up vote down
Breadboard supply - very low dropout adjustable power supplyPowerOct 12, 2024Status0 vote up vote down
Small battery-powered USB charger including circuit diagram and PCB layoutPowerOct 12, 2024Status0 vote up vote down
3.3V / 5V Regulated Power Supply CircuitPowerJul 03, 2024Status2 vote up vote down
Lead-Acid Battery MonitorPower Status0 vote up vote down
Simple switching power supplyPowerJul 10, 2024Status-1 vote up vote down
AC Power MeterPower Status-2 vote up vote down
Assorted power source and control circuitsPowerMar 18, 2024Status-1 vote up vote down
Build A Simple Rechargeable CMOS BatteryPower Status-1 vote up vote down
Build A High Performance Voltage Regulator From Discrete ComponentsPower Status-1 vote up vote down
12 Volt Gel Cell Charger circuit diagramPower Status-1 vote up vote down
Build A 10 Amp 13.8 Volt Power SupplyPower Status4 vote up vote down
Adjustable Voltage Regulator using a 7805 or other fixed linear voltage regulator instead on LM317Power Status-1 vote up vote down
Using Pass Transistors Beef Up Voltage Regulator current outputPower Status-2 vote up vote down
12 volt battery monitor circuit diagramPowerJan 26, 2025Status-1 vote up vote down
12 volt power supply circuit diagramPowerJan 26, 2025Status-1 vote up vote down
5 volt power supply circuit diagramPowerJan 26, 2025Status1 vote up vote down
Battery voltage monitor circuit diagramPowerJan 26, 2025Status0 vote up vote down
LM3914 battery monitor circuit diagramPowerJan 26, 2025Status-2 vote up vote down
Multiple voltage power supplyPowerJan 26, 2025Status-3 vote up vote down
Voltage doubler using a 555 timerPowerJan 26, 2025Status0 vote up vote down
Voltage inverter using a 555 timerPowerJan 26, 2025Status-2 vote up vote down
Simple switching regulator (experimental)PowerNov 16, 2024Status-1 vote up vote down
Build a breadboard power module for integrated circuitsPowerSep 30, 2024Status-1 vote up vote down
DC to AC inverter using a 555 timerPower Status1 vote up vote down
Dual (postive and negative) 12V power supplyPower Status2 vote up vote down
Current booster for 78nn series voltage regulatorsPower Status0 vote up vote down
12V Lead-Acid Battery Monitor using LM3914PowerJan 08, 2025Status0 vote up vote down
Charger for gel lead acid batteriesPowerJan 26, 2025Status0 vote up vote down
Compressor-mate power protection for refrigerators, freezers and air conditionersPowerOct 06, 2024Status0 vote up vote down
High voltage DC generatorPower Status0 vote up vote down
High-Voltage Pulse GeneratorPower Status1 vote up vote down
Automatic 9V NiCad battery chargerPower Status0 vote up vote down
Active Power ZenerPower Status-1 vote up vote down
Solid state relay circuitPower Status-1 vote up vote down
NiCad Discharger for Tx & Rx PacksPower Status1 vote up vote down
Lead acid battery charger with floatPower Status1 vote up vote down
Simple constant current sourcePower Status0 vote up vote down
Nine Volt Battery EliminatorPowerSep 07, 2024Status1 vote up vote down
PWM DC Motor Speed ControlPowerSep 21, 2024Status0 vote up vote down
12 Volt Battery Voltage Monitor (kit available)PowerJun 18, 2024Status1 vote up vote down
Battery Low Voltage BeeperPowerSep 21, 2024Status0 vote up vote down
12 Volt 15 Amp Low Voltage Disconnect (kit available)PowerJun 18, 2024Status-1 vote up vote down
PWM Motor Speed Controller / DC Light DimmerPowerJul 12, 2024Status0 vote up vote down
PWM Motor/Light ControllerPowerJul 12, 2024Status-1 vote up vote down
Low Power LED VoltmeterPowerJul 12, 2024Status1 vote up vote down
WGR1 - 12 Volt Wind Generator RegulatorPowerMay 19, 2024Status0 vote up vote down
Expanded Scale Battery Volt MeterPowerSep 07, 2024Status0 vote up vote down
Temperature Controlled Nicad ChargerPowerSep 21, 2024Status-1 vote up vote down
12V, 4-AA Cell Differential Temperature ChargerPowerAug 17, 2024Status0 vote up vote down
PWM Motor/Light ControllerPowerJan 26, 2025Status0 vote up vote down
PWM Motor/Light Controller variantsPowerJan 26, 2025Status-1 vote up vote down
Low Power LED VoltmeterPowerJan 26, 2025Status0 vote up vote down
Temperature Controlled NICD ChargerPowerJan 26, 2025Status0 vote up vote down
Battery Charger IdeasPowerAug 14, 2024Status0 vote up vote down
Windmill DIY Analog MPPT (maximum power point tracker) CircuitPowerMar 09, 2025Status0 vote up vote down
20 amp (peak) power supply for SSB transceiversPowerJun 24, 2024Status0 vote up vote down
Battery CharacterizerPowerJul 24, 2024Status1 vote up vote down
Lead/acid battery chargerPower Status0 vote up vote down
200 Watt Modified PC Power Supply 13.5 Volt 14 AmpPowerJul 24, 2024Status-1 vote up vote down
12V 30A power supply circuit diagramPowerJan 26, 2025Status-1 vote up vote down
Dual regulated power supplyPowerJan 26, 2025Status-2 vote up vote down
Fuse blown indicatorPowerJan 26, 2025Status1 vote up vote down
Gyrator circuitPowerJan 26, 2025Status0 vote up vote down
LM317 Regulator CircuitPowerNov 27, 2024Status-2 vote up vote down
Nicad battery chargerPowerJan 26, 2025Status0 vote up vote down
Unregulated power supplyPowerJan 26, 2025Status0 vote up vote down
2A power supply - An adjustable power supply for model railways and general projectsPowerJun 28, 2024Status-1 vote up vote down
Broken Charger Connection Alarm CircuitPowerJul 15, 2024Status1 vote up vote down
Safety Guard - Simple unit, Protects home appliances from voltage spikesPowerJul 15, 2024Status0 vote up vote down
Running 12V Fan Directly on 220V ACPowerJul 30, 2024Status1 vote up vote down
Low Voltage Power Supply / step down using a MC34063PowerJul 03, 2024Status1 vote up vote down
A small power supply for universal use based on an LM317 adjustable regulatorPowerJul 03, 2024Status1 vote up vote down
Linear regulated bench power supply 20V, 2A - easy to upgradePowerJul 03, 2024Status0 vote up vote down
Bench power supply with buck converter with a linear afterburnerPowerJul 03, 2024Status0 vote up vote down
Small 2.5 - 50V power supply for universal use based on a LT1074PowerJul 03, 2024Status1 vote up vote down
Linear Power Supply 8 .. 16 V ~ 10A that offers low noisePowerJul 03, 2024Status-1 vote up vote down
Artificial ground to transform an Unipolar Power Supply into a Bipolar Power SupplyPowerJul 03, 2024Status1 vote up vote down
Power Supply 13.8V/20APowerSep 07, 2024Status0 vote up vote down
BattMan II: Build a Computer Controlled Battery ManagerPowerOct 15, 2024Status0 vote up vote down
Build a Low Cost Thermal Peak Detection NiCd ChargerPowerOct 15, 2024Status-1 vote up vote down
Charge-Pump Voltage Doubler with RegulatorPowerOct 20, 2024Status3 vote up vote down
Power Supply LCD meter Display - K1QWPowerOct 20, 2024Status-1 vote up vote down
12V to 110V/220V DC-AC 300W InverterPowerOct 20, 2024Status-2 vote up vote down
1.5V to 5V 200mA ConverterPowerOct 20, 2024Status-2 vote up vote down