AmpStrike – Battery Powered Bench Power Supply
This is a small bench power supply that is powered by two lithium-ion batteries. The project was inspired by Dave Jones from EEVblog but the design is completely mine. The voltage range is 0-20V regulated in 10mV steps and maximum current is 1A with current limit set in 1mA steps.
The power supply runs on a linear voltage regulator built on discrete components. The design of the linear regulator was inspired by the user Amspire from the EEVblog forum. The basic idea is that the Q1 pass transistor and U5A op amp act in a classic voltage regulating loop. U5A gets feedback from the output voltage and acts on Q1 in such a way that the output voltage equals the reference voltage on the inverting input. U5D acts as a comparator and switches the base of Q1 low to set the output voltage to 0V. It acts as a current limiter which is quickly switching on and off the output to maintain the set current limit.
AmpStrike – Battery Powered Bench Power Supply – [Link]