Hi Ron,
Well could you show your circuit too? My calculations tell me about 150ma peak during start up but dropping down significantly later. I am using 36 ohms total series resistance and shooting for 11ma output at 11 volts (1k load), with capacitance.
I guess at some point we could try simulating the more exact circuit. The feedback mechanism of this chip is a little different than most switchers but should work to some degree.
One guess would be that it cant start properly with load so it never gets up to the full operating conditions.
My circuit above as I checked also has around 150mA-160mA peak on start up. I had a current drop right after Rsc at around 8mA on Rd resistor.
Do you suspect that this could be a cycling issue within the IC because of the voltage drop on the output load? Perhaps the current I want is too low for it to properly load the inductor.
Nokia used this IC in their products but I'll assume they had higher currents for step-up and step-down with their products which made it suitable for their applications.
What boost converter do you recommend but not too expensive? Maybe a successor to the mc34063.
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