I'm designing the battery power/charging circuit for the Reform DIY laptop which uses a (big) LiFePo4 cell. For the charger IC I've now settled on ADP5063 as it seems simple and can charge with 1.5A current (more would be even better, but hey...).

The charger's datasheet says it can route 2.1A of current through it's integrated battery isolation circuit. This is not enough to power the system, so I don't want to use the internal isolation and instead implement the load sharing circuit featured in Microchip Application Note AN1149 and some other StackExchange questions. For Mosfet Q2 (in the circuit below), which switches between wall and battery power I chose NDP6020P as recommended in Bil Herd's video on high side power switching using a p-channel Mosfet.

My questions are: 1. Is it OK to basically leave the ISO_Sx of ADP5063 pins unconnected or should I wire them to the load as well? 2. Is this way of load switching "around" this charger sane or can there be adverse effects?

Battery/Wall Power Circuit

  • \$\begingroup\$ I don't see any functional problems with this. You have essentially moved the battery isolation FET external to the ADP5063. However I don't see anything that would limit the battery current if there was a short. \$\endgroup\$ – EE_socal Mar 9 '18 at 23:04

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.