ADC pin input : PPG analyser

Projects
1

I have an analog sensor circuit that has output 1-3V. I want to use ADC function of BOLTIOT module. Can I connect it directly to its ADC pin or should I step it down to 0-1V ?

2

you can not directly connect it with ADC pin of bolt module. because it can withstand only (0-1) volt

1 Like
3

Then how shall I connect it?

4

i search alot on this but didn’t get a perfct solution. you should step down the signal. or use the voltage divider circuit.

5

Hi @swethatsunil.mec,

The best possible thing to do is as per what @rishabhrana081020, said. You should step down the signal.
3 x 1k resistors would be enough for this. The connection which will be required are as follows.

  1. Pin 1 of resistor 1 to your circuit’s output.
  2. Pin 2 of resistor 1 to pin 1 of resistor 2
  3. pin 2 of resistor 2 connected to pin 1 of resistor 3 and A0 pin of the Bolt WiFi module.
  4. pin 2 of resistor 3 connected to GND pin of the Bolt Wifi module, and the GND pin of your circuit.

The Bolt WiFi module will log the values in the range of 341 to 1024. 341 for 1v output of your circuit, and 1024 for 3v output of your circuit.

6

thank you so much; it solved my problem.