Hello everyone. I would be very grateful if you can help me with this circuit I am working on (sch.png).
It consists of a TP4056 charger connected to a 3.7v/3Ah Lithium Ion battery to supply a low battery level indicator and a load (a block of white leds and two fans), through a MT3608 Step Up to raise voltage from 3.7v to 9v.
As it is in the schematic below, I have a Logic Level P-Mosfet to disconnect the battery from the load while charging (Vin=5v). Also, a diode was added between Gate and Source to make Vg and Vs almost the same (Vgs=0) so the transistor is not polarized.
1) Because of this diode, the load is powered by Vin while charging the battery (Vin=5v, Vg=5v) as it is shown in Photo 2.
Is there any trick that I can do with that P-Mosfet or anything else to prevent the load from being powered?
2) While powering the load with the battery (3.7v). If I choose a Logic Level P Mosfet with Vth=-2.4v (considering: Vgs=0-(Vbat - 0.6v)), can I stop battery discharging at 3v to avoid reaching a lower voltage level and damage it?. By default, TP4056 cut-off discharge at 2.4v, but it is too low for a Li Ion battery.
Thank you so much!
Circuit based on:
https://www.best-microcontroller-projects.com/tp4056.html
https://nomadaselectronicos.wordpre...tecargador-con-carga-compartida-load-sharing/
It consists of a TP4056 charger connected to a 3.7v/3Ah Lithium Ion battery to supply a low battery level indicator and a load (a block of white leds and two fans), through a MT3608 Step Up to raise voltage from 3.7v to 9v.
As it is in the schematic below, I have a Logic Level P-Mosfet to disconnect the battery from the load while charging (Vin=5v). Also, a diode was added between Gate and Source to make Vg and Vs almost the same (Vgs=0) so the transistor is not polarized.
1) Because of this diode, the load is powered by Vin while charging the battery (Vin=5v, Vg=5v) as it is shown in Photo 2.
Is there any trick that I can do with that P-Mosfet or anything else to prevent the load from being powered?
2) While powering the load with the battery (3.7v). If I choose a Logic Level P Mosfet with Vth=-2.4v (considering: Vgs=0-(Vbat - 0.6v)), can I stop battery discharging at 3v to avoid reaching a lower voltage level and damage it?. By default, TP4056 cut-off discharge at 2.4v, but it is too low for a Li Ion battery.
Thank you so much!
Circuit based on:
https://www.best-microcontroller-projects.com/tp4056.html
https://nomadaselectronicos.wordpre...tecargador-con-carga-compartida-load-sharing/
