TPS61221 not much better

A project log for Crazy Clock

A replacement controller for Lavet stepper clock movements

Nick SayerNick Sayer 12/03/2016 at 22:050 Comments

Well, I guess the search for an alternative power supply continues. The TPS61221 samples arrived, and they're a little better than the TLV61225, but not much. It still draws over twice as much as the NCP1402 under test conditions.

The NCP1402 circuit had inductors that were 10 times the value of the TPS/TLV recommendations (47 µH instead of 4.7 µH - with 2x22µF output filter caps). I'm almost ready to try putting one of those in just to see what happens (not hoping for much, unfortunately).