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I am developing a circuit which enables me to charge a lithium battery and boost the output voltage up to 5V for a microcontroller. My boost converter is the MT3608, and the charging circuit is the TP4056 board.

Everything is working well, but I would like to disconnect the battery when the USB is connected, in such a way as the boost module doesn’t receive any power supply, and so, the microcontroller would work thanks to the USB port, but not through the boost, in order to reduce the global consumption.

I’m following this schematic, which allow me to select between the USB or battery, but I would like to disconnect the battery when the USB port is connected, and therefore the boost module won’t work.

schematic

“USB o Fuente”: It is the USB connector.
“Circuito cargador”: It is a charging circuit like the TP4056 board.
“Circuito aplicacion”: It’s my load, a microcontroller in my case.
“Canal P”: It means a common P-channel MOSFET.

I would really appreciate it if someone could show me a schematic that solves my problem.

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    \$\begingroup\$ Just to verify, since I'm not familiar with... looks like Spanish?, "USB o' Fuente" is a USB connector, "Circuito Cargador" is some type of charging circuit, "Circuito Aplicación" is your load, and "Caral P" is just an ordinary P-channel FET. Is that all correct? \$\endgroup\$ – Hearth Mar 17 at 20:15
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    \$\begingroup\$ Yes, it is exactly as you have said. The schematic is from a Spanish web site (it doesn’t bellow to me). I foget to translated it before posting it. “USB o Fuente”: It is the usb connector. “Circuito cargador”: It is a charging circuit like the TP4056 board. “Circuito aplicacion”: It’s my load, a microcontroller in my case. “Canal P”: It means a common mosfet p-channel. \$\endgroup\$ – Geniux Developer Mar 17 at 20:52
  • \$\begingroup\$ Are you sure you want to remove power to the boost module? I assume your battery is there for backup purpose, avoiding glitches on transitions will be your main concern I think. One thing you could do is keep your boost always On, but give it a set point just below the USB line (100mV-200mV below it maybe), enough to keep your application working. The regulator will saturate and no energy will go through the boost until the actual voltage drops. Also, looking at your schematic, I believe Source and Drain of your P-Fet should be reversed. \$\endgroup\$ – Pier-Yves Lessard Mar 18 at 3:00
  • \$\begingroup\$ I want to remove the power to the boost module when the usb is connected, because I want to achieve that all the circuit works thanks to usb. I want a effect similar to a relay, I means, disconecta the battery when the usb is connected \$\endgroup\$ – Geniux Developer Mar 18 at 9:54

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