Other Parts Discussed in Thread: TPS61023, , TPS61030, TPS63811
I need a boost converter for a 3.7V, 1A load (not switch current!) from a single LiPo cell that we want to run down to 3.0V. We also need this to operate when the system is being operated from a fresh battery at up to 4.35V VIN. The load can operate from 3.4V to 4.5V.
It looks like the TPS61023 would work, but I like the switch specs and availability of the TPS61236P a lot better. Would it work in this application? I think I don't care about CC mode.
The risk seems to be that the TPS61236P would enter pass-through when the battery voltage drops to near 3.7V. We could run at a higher voltage, up to 4.5V, to help avoid that; then we should stay out of pass-through if VIN is 3.9V or higher, and if it's that high and we lose up to 0.4V we might be ok. Given the low rDS(on) of the high-side switch, and choosing a low DCR inductor, I think we could keep the FET+inductor to 100mOhms or less, which should only cause about 0.1V of drop from Vin. But how low from the target VOUT does VIN have to fall before resuming switching? The full 0.6V?
The TPS61030 also looks like an option, but doesn't mention a pass-through mode at all.
What do you suggest? Thanks!