I have built up a test boost regulator as per the datasheet (including layout). I have a variable PSU as input supply and a 270R resistor as load.
In bypass output duly follows input, in boost mode regulator switches ok, but output stays 0.2-0.3v lower than input, irrespective of input.
What am I missing?
Design target is a microprocessor system running from 2x AA batteries switching a 3V latching Relay, (will operate down to 2.5V, objective is to turn on boost reg when batteries are low and relay needs to switch - current requirements 50-60ma normally and additional 9ma when switching relay processor will run down to 1.8V so aiming to boost from 1.8 to 3v to ensure relay operation.
Steve