1.2V-32V DC @ 5Amp Adjustable Power Supply Using LM338K


1.2V TO 32V Power Supply Schematic, PCB Layout

This project provides a variable output voltage ranging from 1.2 to 32 V @ 5 A. Project based on LM338K IC, LM338K is adjustable 3 terminal positive voltage regulator capable of supply in excess of 5A over a 1.2V to 32V output range, simple circuit consist few components.



  • Input Supply : 24 VAC or 30 VDC, 5 Amp
  • Output : variable output from 1.2 to 32 V @ 5 A regulated low ripple DC voltage
  • Heatsink for regulator IC
  • Onboard bridge rectifier to convert AC to DC
  • LED indication at input of IC
  • Thermal overload/short circuit protection (provided by IC feature)
  • Screw terminal connector for easy input and output connection
  • Berg connector for connecting potentiometer (POT) to the PCB
  • Filter capacitors for low ripple DC output
  • Four mounting holes of 3.2 mm each
  • PCB dimensions 91 mm x 66 mm


8 Pin SMD SO8 PIC Micro-controller Development Board (PIC12F683)


8 PIN SMD PIC development board is a full-featured development board and platform for 8-bit PIC® micro controllers. This kit is a versatile development solution, featuring several options for external sensors, off-board communication and human interface. Additionally, it offers ample room for expansion, making it an excellent solution for developers and engineers looking for a… The 8 Pin SO8-SMD PIC Development / Evaluations Board demonstrates the capabilities of Microchip’s 8-bit micro controllers, specifically, It can be used as a standalone demonstration board with a programmed part. With this board you can develop and prototype with all Microchip’s 8 PIN PIC micro controllers which doesn’t required crystals (External Oscillator). On board connector for ICSP allows an easy programming. The board has configurable pull ups on all pins can be soldered or abandon as per requirement, All pins has solder Jumpers for pull down.  Onboard 5V regulator, two tact switch, one output connector to interface with 12V Relay board or solid state AC or DC Relay. Board has small prototype area. We have considered PIC12F683 IC for this Board.



  • Supply 6V to 12V DC
  • On Board ICSP Connector for Programing
  • 3 Pin Output Header Connector for Relay or Solid State Relay
  • All Pin has pull up resistors can be solder as per requirement
  • All Pins has solder Jumper for pull down
  • ON Board 5V Regulator
  • On Board 2 tact switches
  • Small Proto Area
  • 3 Parallel Header Connectors connected to pin 2, 3, 4, 5, 6, 7



8 PIN SO8 PIC Development Board Circuit

8 PIN SO8 PIC Development Board Circuit and PCB Layout PIC12F683

8 PIN SO8 PIC Development Board BOM

8 PIN SO8 PIC Development Board BOM PIC12F683, PIC12F675

8 PIN SO8 PIC Development Board PIC

8 PIN SO8 PIC Development Board PICA

Dual Adjustable Power Supply +/- 1.2V to 30V DC. 1.5Amp


This project is a solution to power up most of devices or projects required dual (+/-) adjustable power supply. The circuit is based on LM317 positive and LM337 negative voltage regulator. LM317  series of adjustable 3 terminal regulator is capable of supplying in excess of 1.5A over a  1.2V to 30V DC output range, due to TO3 package of  IC and large heat sink the power supply can handle maximum load  current.

Output: +/- 1.2 to 30V DC
Output Current: 1.5Amps
Supply Input: 24V-0-24V AC, 2Amps Center tape Transformer
CN1: Transformer Connections
CN3: +/- Dual Supply Outputs
P1: Positive Voltage Adjust
P2: Negative Voltage Adjust
D1: Positive Power Indicator
D2: Negative Power Indicator







image description


Two Channel Relay Board

twochannel relay board

2 channel Relay driver project can be controlled by feeding 2-12V trigger voltage, Very useful project for application like Micro-Controller based projects, Remote controller, Lamp on Off, and any circuits which required isolated high current and high voltage switching by applying any TTL or CMOS level voltage. Two LED works as operation indicator while in , 3 pins screw terminals to connect load and provides  both normally open and normally closed switching.





  • Input: 12 VDC @ 84 mA
  • Output: Two SPDT relay
  • Relay specification: 5 A @ 230 VAC
  • Trigger level : 2 to 12 VDC
  • Header connector for connecting power and trigger voltage
  • LED on each channel indicates relay status
  • Power Battery Terminal (PBT) for easy relay output connection
  • Four mounting holes of 3.2 mm each
  • PCB dimensions 49 mm x 68 mm


Two Channel Relay Board

Light Sensitive Switch Single Transistor Based

Light Sensitive Switch is a simple project which operates a relay when light falls on the LDR.

Input : 12 V @ 55 mA
Relay output : NC-C-NO
Onboard preset to set the level
Power-On LED indicator
Relay On LED indicator
Power Battery Terminal (PBT) for easy relay output connection
Four mounting holes of 3.2 mm each
PCB dimensions 44 mm x 49 mm



Light Sensitive Switch Schematic

Light Sensitive Switch Schematic


Light Sensitive Switch PCB and Parts List

Light Sensitive Switch PCB and Parts List

LED VU Meter 5LEDs CH1403 or LB1403 IC


5 LED VU Meter project is based on LB1403/CH1403 IC from SANYO, which will indicates the volume level of the audio signal it senses.


 Power supply : 6 to 12 VDC @ 90 mA
Lighting levels remain stable to line regulation because of on-chip voltage reference
LED’s are driven by a constant current
Onboard presets to adjust input sensitivity
Terminal pins for connecting power supply, audio input
Four mounting holes of 3.2 mm each
PCB dimensions 34 mm x 52 mm



Tiny Mic Pre-Amplifier


The Tiny Mic Pre-Amplifier project is based on a single transistor.  It amplifies the output of the electret condenser microphone. The project amplify low level signal coming from microphone and then provide sufficient voltage level to drive power audio amplifier. Good choice for Karaoke.

Power supply : 5 ~ 9 VDC @ 2 mA
PCB dimensions 26 mm x 56 mm




Mini Stereo Audio Amplifier TDA2822


Mini Stereo Audio Amplifier project is designed for portable radio players and other building block projects.  It is based on TDA2822 IC.


 Power supply : Upto 12 VDC
 Output : 1 W, 8 ?  for 12 VDC / 20 mW, 32 ? for 3 VDC
 Input resistance 100 K?
 Low crossover distortion, Low quiescent current
 Berg connector for connecting audio input, power supply and outputs
 Onboard Presets to adjust volume
 Power-On LED indicator
 Four mounting holes of 3.2 mm each
 PCB dimensions 50 mm x 36 mm



1 44 45 46 47 48 49