ESP8266 Community Forum

- Thu Jun 09, 2016 1:45 am #48845 Hi, I've got 10 boards running the AMS1117-3.3's from 12v. One let out the magic smoke and had to be replaced the others run about 60 Deg C but have been fine. Just for referance: Both the middle pin and the tab are Vout (3.3V) just check thats not grounded. A good little workhorse but it does seem there are some bad ones around.

- Mon Jun 13, 2016 12:46 pm #49132 I just tried one of the AMS1117's without anything else connected to it. I only got 2.8v out of it, soe it seems they are not of great quality anyway, but it should not be a reason to burn through.

The odd thing is that when I measure all connections with a multimeter, there doesn't seem to be any short-circuits. But when measure it with the ESP on it, it looks like there's a short circuit between vgg and GND. When I measure a ESP that's not soldered on, that short circuit does not exist. You would almost think that I have a bogus esp module (Or I destroyed it already somehow).

Below is the PCB in question. I's basically a breakout board for the i2c bus and 1-wire. I have a lot of pullups on there, as well as quite some capacitors, but for now I've only tested it without any of those on it, which should in theory be enough to get the ESP started.

If anyuone can spot a error on the PCB, I's be happy to know

- Mon Jun 13, 2016 12:54 pm #49133 On the bottom side, the uppermost I2C connector clearly shows that SDA and SCL are shorted ...

- Mon Jun 13, 2016 1:21 pm #49135 Thanks Martin, so obvious
I measured all Gnd and vcc connections, but did not measure between sda and scl.

Guess its back to the drawing board,but first I give cutting the wrong line a try.

Last edited by ErikLem on Mon Jun 13, 2016 2:45 pm, edited 1 time in total.