ESP8266 Community Forum

- Fri Sep 02, 2016 1:22 am #54304 Did you read my first post?

Especially this part:
"Do you have also the proper input and output Voltage regulator capacitors in place? "

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- Fri Sep 02, 2016 3:27 am #54309 Hi - I would do a few tests to check wether you have a incorrectly marked IC. The dropout for that series is about 1.3V, so I would up the supply voltage to 7 or above volts and see if it still regulates to 5V. Then I would load it up and draw about 500mA to see what voltage it regulates to - if this also remains at 5V I would diduce that you have a incorrectly marked IC.

- Fri Sep 02, 2016 7:59 am #54315 While not having capacitors in the circuit is bad when it comes to running the completed circuit I don't believe the lack of them would cause an incorrect output voltage of the degree he is reporting. But I have seen power supplies that have a high frequency oscillation riding on the dc output. And that was from a Tektronix power supply module, but from long ago. I think it was using a 7800 series regulator.

- Fri Sep 02, 2016 10:04 am #54319 The only explanation I can think of is incorrect connections to Gnd-Vout-Vin. Also note the tab is connected to Vout, the center pin.

Not having capacitors would not yield such erroneous results, at least not in simple voltage measurement tests.