ivp wrote:
> With 3.8V in / 5V out, the circuit is drawing around 15uA without
> a load from Vout to V
>
> 4k7 (1.07mA load) draws 1.51mA from the battery
> LED + 680R (4.87mA load) draws 6.69mA
> 1k (5mA load) draws 6.96mA
> LED + 1k (9.87mA load) draws 13.65mA
>
> Efficiency is a pretty consistent 72%. I expected > 90%

At these low voltages, the diode drop becomes significant.  Is the diode a
schottky?  If not, make it so.  If so, is this chip capable of syncronous
rectification?

10uH sounds rather low unless you have a fast switching frequency, probably
around 1MHz or at least over 500KHz.  Otherwise, the inductor is unlikely
where the lost power is being dissipated.


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