SIM800C Power Supply Issue

Hello Sir,

I’m using sim800c breakout board there is input pin 5V VCC , separate boost converter circuit is also there.
When I’m powering it with my USB TTL CP2102 Module , The module continuously Restarting…
Is boost converter compulsory… for sim800c… or any alternative is there to test it with usb port…

I’m using this module to test dtmf service…

Thankyou in advance…

Hi,
You cannot connect USB TTL CP2102 Module to computer to feed SIM800c. You must use an external source power that gives more than 2A.
But even so the problem can persist, cause the 5V pin doesn’t work as expected in many situations.
I gave up to power my module through the 5V pin, and my work around was to applay the voltage (3.8V to 4.0V) to VBAT, using LM2596.
I tried to short circuit the two diods that protect the module, and feed the 5V pin with 3.8V, but this didn’t work for me.