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I have a project on small pocket board with a Li-Ion battery so I made a pcb with power section based on a tp4056 board (with protection), with LP2985IM5X-3.3 stabilizer. TP4056 charges the Li-ion and it works good, on the out I have 3.6V, but when I turn on the stabilizer before it is 0.6V and next to it is ~0.2 - 0.6V. I have no idea how to fix it to work on the 3.3V level. Please, write to me some suggestions. Thanks.

Schematic of power section: enter image description here

Edit:

I changed MOSFETs connection (look comments) and voltage is fine, everything works good but there is one problem, it doesn't charge li-ion.

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  • \$\begingroup\$ How much current are you trying to draw from the regulator? \$\endgroup\$ – Ignacio Vazquez-Abrams Mar 15 '17 at 16:58
  • \$\begingroup\$ @IgnacioVazquez-Abrams I'm going to get max 100mA. PS: I tried this only with microcontroller, maybe it is to low current and regulator donot work good ? \$\endgroup\$ – Sewek Mar 15 '17 at 17:21
  • \$\begingroup\$ That regulator should be fine down to single-digit mA. \$\endgroup\$ – Ignacio Vazquez-Abrams Mar 15 '17 at 19:48
  • \$\begingroup\$ Ok. My mistake. MOSFET A should go to pin 1 and MOSFET B to pin 3. Now voltage is correct. But there is another problem, it doesn't charge li-ion \$\endgroup\$ – Sewek Mar 18 '17 at 9:03

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