As mentioned in the heading, this is a positive section bench power supply based on Kerry Wong's supply. I've made some changes to suit 3A current and reduced the voltage control to match a 2.048V DAC and precision external reference for the ATMega328p which will handle control and display on I2C 16x2 LCD.

The +12V, -12V, +5V supply will be off the board and shared between up to three modules, I've yet to design this.

I've posted up TINA-TI simulation model of the linear section and the corresponding schematic for the module. Any comments welcomed.

OSH render of the rev A2 design