I want to put togther a cheap nasty smps to power a project.
A 555 is used as the circuit is usb powered, the circuit works well as a 2 switch forward converter but I want a dead simple single switch so I need a 50% duty o/p from the 555 with good accuracy.
I saw somewhere a diode from discharge to trigger, is this going to work?
Edit: I shouldnt be so lazy, looking at the schem its clear to see that the timing cap charges up through the resistor to + and the forward biased diode, then the cap discharges through the resistor between trigger and discharge with the diode reversed, if if the 2 resistors are the same duty should be 50%, I must have poxy resistors or something as I get 60%.
A 555 is used as the circuit is usb powered, the circuit works well as a 2 switch forward converter but I want a dead simple single switch so I need a 50% duty o/p from the 555 with good accuracy.
I saw somewhere a diode from discharge to trigger, is this going to work?
Edit: I shouldnt be so lazy, looking at the schem its clear to see that the timing cap charges up through the resistor to + and the forward biased diode, then the cap discharges through the resistor between trigger and discharge with the diode reversed, if if the 2 resistors are the same duty should be 50%, I must have poxy resistors or something as I get 60%.
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