Hack Into a Timer AC Socket [Continued]Chao
In the last post, the problem finally concluded is the circuit in the socket can not provide enough current to support the bluetooth module, according to the equation, it is probably only 22mA, so these items are bought to replace the original parts:
- 0.33uf safety x2 capacitor to 1uf cap.
- 1M discharge resistor are now paralleled connected with other 1M resistor, so the final resistor value is 0.5M, but 0.2-0.3K should better, for testing we leave it.
And there is the second change: The tested voltage on the IC only 2.77V, so we lower down divider resistor from 2K to 500R, now the supplied voltage at 5V successfully.
The bluetooth module we used is BC04-C, no need other controlling MCU, directly IO controlling. VCC, GND, and GPIO11 (last IO) is connected into the AC socket, GPIO11 is just before the switching transistor.
It is a pretty dangerous work for AC, must be careful.
This is not a ideal embedding work, because the AC socket output a constant voltage and current, which is great for LEDs or this product, but the bluetooth normally use a variable current. On the other hand, there are also too many replacing work.
See the demo video here: