Isolated Power Supply for RS485, RS422, RS232, SPI, I2C and Power LAN

  • Rajkumar Sharma
  • 8346
  • easy
  • Tested

Mini Isolated Power Supply is designed for CAN, RS-485, RS-422, RS-232, SPI, I2C, Low-Power LAN applications. The power supply provides +/- 5.50 V DC symmetrical outputs with load current 500mA from 5V DC input. The project is built using SN6505A IC from Texas instruments. The SN6505A is a low-noise, low-EMI push-pull transformer driver, specifically designed for small form factor, isolated power supplies. It drives low profile, center-tapped transformers 5 V DC power supply. Ultra-low noise and EMI are achieved by slew rate control of the output switch voltage and through Spread Spectrum Clocking (SSC). The SN6505 consists of an oscillator followed by a gate drive circuit that provides the complementary output signals to drive ground referenced N-channel power switches. The device includes two 1-A Power-MOSFET switches to ensure start-up under heavy loads. The internal protection features include a 1.7A current limiting, under-voltage lockout, thermal shutdown, and break-before-make circuitry. SN6505 includes a soft-start feature that prevents high inrush current during power up with large load capacitors.


  • Input Supply 5V DC
  • Output +/- 5.50 V DC symmetrical outputs
  • Output Current 500mA Approx.
  • Ultra-Low EMI
  • Spread Spectrum Clocking
  • Precision Internal Oscillator Options: 160 kHz (SN6505A)
  • Slew-Rate Control
  • 7 A Current-Limit
  • Low Shutdown Current: <1 μA
  • Thermal Shutdown
  • Wide Temperature Range: –55°C to 125°C
  • Soft Start to reduce In-rush current


  • Isolated Power Supply for CAN, RS-485, RS-422, RS-232, SPI, I2C, Low-Power LAN
  • Low-Noise Isolated USB Supplies
  • Process Control
  • Telecom Supplies
  • Radio Supplies
  • Distributed Supplies
  • Medical Instruments
  • Precision Instruments
  • Low-Noise Filament Supplies


Parts List




Notify of
Inline Feedbacks
View all comments


Arduino Nano 33 IoT Giveaway

By continuing to use the site, you agree to the use of cookies. more info

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.