×

13V 20A High-Current Power Supply Using BUZ11, 7812, and 2N5683

This high-current DC power supply provides a regulated 13V output at up to 20A. The design uses a BUZ11 MOSFET for high-current switching, a 2N5683 transistor for current amplification, and a 7812 voltage regulator for precise voltage reference and control.

Power Supply Requirements

  • Input voltage must be sufficient to supply 13V DC under full load.
  • The power supply should handle up to 20A of load current safely.
  • Proper heatsinking is required for BUZ11, 2N5683, and 7812 to dissipate heat.

Key Components

  • BUZ11 MOSFET: Handles high output current efficiently and acts as a pass device for the main supply.
  • 2N5683 Transistor: Provides additional current amplification and control for stable output.
  • 7812 Voltage Regulator: Supplies a precise 12V reference for the control circuit, which is slightly boosted to achieve 13V output.
  • Filter Capacitors: Smooth the DC output and reduce voltage ripple.
  • Resistors: Set the biasing and current limiting for the transistor and MOSFET stages.

Circuit Operation

  • The 7812 regulator provides a stable 12V reference voltage to control the output stage.
  • The 2N5683 transistor amplifies the control signal to drive the BUZ11 MOSFET at high current.
  • The BUZ11 MOSFET acts as a pass element, supplying up to 20A to the load with minimal voltage drop.
  • Filter capacitors smooth the output to ensure stable 13V DC with low ripple, suitable for high-current applications.
  • The design ensures that the output voltage remains regulated even under varying load conditions.

Key Features

  • Regulated 13V DC output at up to 20A
  • High-current pass stage using BUZ11 MOSFET
  • Voltage reference provided by 7812 regulator
  • Additional current amplification with 2N5683 transistor
  • Low ripple and stable output for sensitive electronics
  • Suitable for battery charging or high-current DC loads

Construction Notes

  • Mount BUZ11, 2N5683, and 7812 on appropriate heatsinks using thermal paste to ensure proper cooling.
  • Use thick wires or copper busbars for high-current output connections to prevent voltage drops.
  • Check transistor and MOSFET pinouts carefully before soldering.
  • Include sufficient filter capacitance to maintain stable output under dynamic loads.
  • Test the supply gradually with lower currents before applying full 20A load to ensure safe operation.
  • Consider adding a fuse or circuit breaker for overload protection.
13 Volt 20 Amp DC Supply