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Think I just burned out my first cp2102

PostPosted: Sat Dec 12, 2015 2:53 pm
by AJB2K3
Think I just burned out my first cp2102
It power up, both the transmit on it and the esp 01 flash then the lights go out and it dissapears from both the win an osx hardware managers.

Re: Think I just burned out my first cp2102

PostPosted: Sat Dec 12, 2015 4:00 pm
by lethe
Don't power the ESP from the 3.3V output of your serial adapter (I assume that's what you were doing).
Most serial adapters will not supply enough current to the ESP and either brown out the ESP or the serial adapter. Try using a dedicated 3.3V suply.

Re: Think I just burned out my first cp2102

PostPosted: Mon Dec 14, 2015 5:11 pm
by Timpanogos Slim
lethe wrote:Don't power the ESP from the 3.3V output of your serial adapter (I assume that's what you were doing).
Most serial adapters will not supply enough current to the ESP and either brown out the ESP or the serial adapter. Try using a dedicated 3.3V suply.


The cp2102 can do it, *if it is implemented correctly. That probably comes down to how generous the power traces on the board are, and the use of appropriate bypass capacitors.

Disappearing from the hardware manager sounds like it drew more power than the usb port was prepared to deliver, though.

Re: Think I just burned out my first cp2102

PostPosted: Mon Dec 14, 2015 6:50 pm
by lethe
Timpanogos Slim wrote:The cp2102 can do it, *if it is implemented correctly. That probably comes down to how generous the power traces on the board are, and the use of appropriate bypass capacitors.

The CP2102 regulator's max. output is 100mA, the ESP's power consumption while transmitting is 130-170mA on average according to the datasheet. No amount of capacitance can compensate that for continous transmission (and you can't control how much your ESP is transmitting, since it will reply to ping requests).
Also adding large amounts of capacitance will result in a high inrush current, that may exceed USB specifications. So you should be careful about adding large amounts of capacitance to your USB port.

Disappearing from the hardware manager sounds like it drew more power than the usb port was prepared to deliver, though.

The CP2102 is powered by its own regulator, so overloading that will also cause the device to brown out and drop off the bus. Either option is possible...