3 Amps power operational amplifier using lm675

Power operational board can drive high current load up to 3Amps, the board helpful to drive Dc Motor, solenoid, Lamp, LED and industrial application. The project built around LM675 power op-amp from texas instruments. All resistors are 1%. Refer datasheet of LM675 for further information.

I Output= VIN X 2.5amps/volt

i.e Iout=1A when VIN=400mV

Trimmer Pot for Max Rout

Download PDF PCB Layout

The LM675 is a monolithic power operational amplifier featuring wide bandwidth and low input offset voltage, making it equally suitable for AC and DC applications.

The LM675 is capable of delivering output currents in excess of 3 amps, operating at supply voltages of up to 48V. The device overload protection consists of both internal current limiting and thermal shutdown. The amplifier is also internally compensated for gains of 10 or greater.


  • 3A Current Capability
  • AVO Typically 90 dB
  • 5 MHz Gain Bandwidth Product
  • 8 V/μs Slew Rate
  • Wide Power Bandwidth 70 kHz
  • 1 mV Typical Offset Voltage
  • Short Circuit Protection
  • Thermal Protection with Parole Circuit (100% Tested)
  • 16V–48V Supply Range ( +/-12 To 24V DC)
  • Wide Common-Mode Range
  • Internal Output Protection Diodes
  • 90 dB Ripple Rejection


Original Circuit from Texas Instruments Data Sheet

Lm2596-ADJ Buck Regulator output adjustable 1.2v to 35v load up to 3amps

High efficient and compact project is capable of driving a 3Amp load with excellent line and load regulation with output adjustable 1.2V to 35V DC.  The project built around LM2596ADJ regulator which is ideally suited for easy and convenient design of step-down switching regulator using buck converter topology. Adjustable output version of LM2596 is internally compensated to minimize the number of external components to simplify the power supply design. PCB dimensions 39.65 X 33.20MM


  •     Adjustable Output Voltage Range 1.23 V 35 V
  •     Guaranteed 3.0 A Output Load Current
  •     Wide Input Voltage Range up to 40 V
  •     150 kHz Fixed Frequency Internal Oscillator
  •     Thermal Shutdown and Current Limit Protection
  •     Internal Loop Compensation
  •     Moisture Sensitivity Level (MSL) Equals 1


  •     Simple HighEfficiency StepDown (Buck) Regulator
  •     Efficient regulator for Linear Regulators
  •     OnCard Switching Regulators
  •     Positive to Negative Converter (buck-boost)
  •     Negative StepUp Converters
  •     Power Supply for Battery Chargers

Bill Of Material
R1 4K7 SMD 0805
R2 1.21K 1% SMD 0804

5V & 12V Output DC-DC Converter with large current relay for cnc driver (Mach3)

Single Channel Large current relay board with dual DC-DC converter board is mainly designed for Hobby CNC, Routers, and Plasma cutters. Hobby CNC controller required multiple DC outputs to drive several things.  This board provides 5V DC and 12V DC 1Amp each. The dual supply helps driving LPT breakout board, Sensors, Limit switches and few other things required 5V and 12V.

The Relay has large current handle capacity can be used to drive spindles, solenoids, water pump, chiller,  The relay required TTL High signal to trigger or it has the facility to even trigger with GND signal.

Important project for CNC Hobbyist Mach3, Mach4 based CNC drivers 


  • Supply Input 15V to 35V DC
  • DC Outputs 5V @ 1A & 12V 1A
  • On-Board LED for Relay Output
  • Relay Contact 20Amp NC and 30 Amps No 230V AC
  • Relay Trigger 5V TTL in or GND input
  • Screw Terminal and 2 Pin Header Connector Provided for Supply Input
  • Screw Terminal and 2 pin header provided for 5V DC & 12V DC Output
  • 3 Pin Screw Terminal Provide for Relay output Connections NO/NC
  • 3 Pin Header Connector for TTL + Signal Trigger, and Low GND signal Trigger
  • Close The Jumper to trigger rely with low GND signal input

High Precision Low Cost Adjustable Constant Current Source Output 0 to 2.5A

Current sources are widely used in industrial, power supply, LED drivers and other equipment. The project has been developed using the AD8276 difference amplifier and the AD8603 op-amp. Current source using the low power AD8276 difference amplifier and the AD8603 op amp are affordable, flexible, and is small in size. Performance characteristics such as initial error, temperature drift, and power dissipation make the AD8276 and the AD8603 ideal candidates for such project. The circuit provides current 0 to 2.5Amps, input supply 12 to 15V DC. I have tested this board with 4.7E/10W X3 parallel resistors.

Download PDF Schematic

Download AD8276 Data Sheet

Download AD8603 Data Sheet


  • Input 12 to 15V DC
  • Load Current Up to 2.5Amps
  • Current Adjustable 0 to 2.5Amps
  • On Board Trimmer Pot to Adjust the Current
  • Required Large Size Heatsink for full load 2.5Amps

3Amps Adjustable Power Supply Provides 1.2V to 15V DC LM1084-ADJ

Simple power supply circuit provides variable output voltage 1.2V to 15V DC and load current up to 3 Amps, onboard trimmer pot provided to adjust the output voltage. Output capacitor C3, C4 provided for transient response, the circuit can take DC input as well as AC input, maximum DC input 15V DC and AC input 12V AC. LM1084-adj IC is heart of the project.

LM1084-ADJ Data Sheet


  • Output 1.2V to 15V DC
  • Input DC 15V DC
  • Input AC 12V AC
  • Load Current Up to 3Amps

Note : The project also can be used with LM1085-ADJ, LM1086-ADJ, AND LM317-ADJ

Note : Higher input and output volatge possible with few changes, input filter capacitor volatge , higher current bridge rectifier can provide higher current up to 5amps with LM1084-adj. refer data sheet of LM1084-ADJ



The LM1084 is a regulator with a maximum dropout of 1.5 V at 5 A of load current. The device has the same pinout as TI’s industry standard LM317.

Two resistors are required to set the output voltage of the adjustable output voltage version of the LM1084. Fixed output voltage versions integrate the adjust resistors.The LM1084 circuit includes a zener trimmed bandgap reference, current limiting, and thermal shutdown.

Refer to LM1085 for the 3A version, and the LM1086 for the 1.5A version.

60V to 5V-2Amps USB Power Output DC-DC Converter for E-Vehicle

Tiny 60V to 5V USB power converter is based on TPS54560 IC, the projects provides 5V DC and peak current up to 5Amps, constant current up to 2Amps. It can be used in lots of application where high voltage to 5V DC USB power required, good use in automotive application. It can be used in E-vehicle for smart phone charger,  USB Hub connector mounted on board for easy connection, input has screw terminal.

Download Data Sheet TPS54560


  • Supply input 9V to 60V DC
  • Output 5V DC
  • Load Current 5 Amps Peak and 2Amps Constant
  • Onboard USB Hub Connector
  • Good for E-Vehicle, Carts, Trucks as for USB Charger

Watch Video Of This Project

High Voltage Low EMI Power Supplies for AC Inverters and VF Drives, Brush-Less Motor Drivers

The high voltage high current low EMI, power supply circuit published here is intend use for AC inverters and VF drives,AC servo driver, brushless dc motor driver, IPM (Intelligent Power Module) , high voltage DC brushed motor drivers and various other circuit required high voltage DC supply.   Capacitor has been selected for AC power input up to 250V AC however capacitor voltage and value can be alter as per DC output required.  Bridge rectifier can handle current up to 25Amps and need large heat sink for full load. Onboard transformer used as EMI fliter.

  • AC Supply input up to 250V V AC
  • Maximum DC Output 400V DC and 10Amps.
  • DC Supply Output will depend on input supply
  • Fuse for Short circuit and over current protection
  • Fuse as per your application requirement Maximum 10Amps Fuse
  • NTC provided for inrush current
  • DC Bus has bleeding resistor








Power Supply for Hi-Fi Audio Amplifier – Symmetrical Output Including +/-15V DC Output

The power supply has been designed to use for audio power amplifiers. This power supply uses a transformer, a bridge rectifier, various rail capacitors, fuse for protection, also supply has separate dual regulators for +/-15 V DC output.  Maximum output for main audio amplifier +/-42V DC, high voltage output possible by altering bus capacitor voltage. The power supply also provides +/-15 V DC to power up pre-amplifier or other support circuit required symmetrical low regulated voltage. Replace LM7815/LM7915 IC with LM7812/LM7912 if need +/-12V regulated output. NTC used for inrush current at power on. All inputs and outputs provided with Screw terminals for easy connections. Project can provide Load current up to 10Amps for amplifier and +/-15V 500mA for pre-amplifier. R2 and R3 resistor used to discharge the capacitor at power off.

Note 1 : Default Bus capacitor value used for 30-0-30V AC Transformer, For higher voltage output use appropriate capacitor voltage. 

Note 2 : Short the EMI transformer T1 terminal using jumper wire as shown in circuit  (Transformer not required for Audio amplifier)

Note 3 : Advisable to use Chassis earth connection, Tie ETH terminal to amplifier chassis


  • AC Input 30-0-30V AC 10Amps Center Tape Transformer
  • AC Input 12-0-12V 500mA
  • +/-42V, 10Amps DC Output ( Unregulated)
  • +/-15V , 500mA DC Output ( Regulated) for Pre-Amplifier and Biasing Circuit











1.2V To 37V, 3Amp Adjustable Power Supply Using LM2576

This regulator board delivers 3Amp current and adjustable voltage range 1.23V to 37V, with input voltage 40 V.The board built around LM2576-ADJ from Texas instruments. A 3.0 A output current capability power supply that features an adjustable output voltage,  In order to achieve a 10 or more times reduction of output ripple. LM2575ADJ IC also can be used in same project if output current requirement is low as 1Amp.LM2576HVT-ADJ IC Can help to provide higher voltage output range 1.2V-50V @ 3Amp current.


  • Output 1.2 to 37 VDC @ 3 A
  • Onboard Trim-Potentiometer for output voltage adjust
  • On Board Power LED
  • Header Connector For Input & Output
  • Adjustable Version Output Voltage Range, 1.23 to 37 V +/-4%
  • Maximum Over Line and Load Conditions
  • Guaranteed 3.0 A Output Current
  • Wide Input Voltage Range 40V
  • 52 kHz Fixed Frequency Internal Oscillator
  • TTL Shutdown Capability, Low Power Standby Mode
  • High Efficiency
  • Thermal Shutdown and Current Limit Protection









Download Data Sheet LM2576ADJ

Download Data Sheet LM2575ADJ


LM2576HVT Based Circuit can provide higher voltage output Range 1.2V to 50V DC , current upto 3Amps



12V To 24V, 1Amp Step Up DC-DC Converter Using LM2588

12V To 24V Booster is based on LM2588-ADJ IC from Texas Instruments. The LM2588-ADJ regulator integrated circuit specifically designed for fly-back, step-up (Boost) , and forward converter. The board provides 24V DC 1A DC output, Input 8V to 16V DC. project  has minimum components, screw terminal provided for input & outputs.

Note : Use LM2588-ADJ IC


  • Supply Input 8V To 16V DC ( Ideal 12V DC)
  • Output 24V 1A










Download LM2588 Data Sheet


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