Hi, Im using this chip becuase its small and cheap,
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however being the heretic type of dc-dc switcher converter at low loads it screeches a lot wich is annoying, is there a better solution wich has integral power switch in a cheap so8 or smaller package ? idealy current mode or voltage mode, or has anyone got a way of making these things behave better at low loads ?
Im using it as a step up converter to provide 250v and -25v from a 12v supply, the 250v is used to drive an EL lamp via a class d stage, the -25 for the lcd neg bias.
so about 3w total.
otherwise it all works fine just the audio screech when the EL is off realy anoys me, seems when the voltage drops allowing the thing to start it gives a high duration pulse, the short flyback pulse doesnt realy change the output voltage much so the next pulse is max duration and the inductor hasnt demagnetised so the next flyback pulse is a dusey, the thing then misses many pulses, hence the audio screech.
Colin =^.^=