Hello,
I have designed two boards , a base and a sheild.
The base board has an esp32 wroom 32D, it has a lora module and a rtc. it also has the cp2104 usb chip .
the shield has leds , 2 super capacitor 1.5F each. The shield has an ads1115 which is used to measure
the voltage from the super ...
Search found 7 matches
- Sat Jun 07, 2025 12:34 am
- Forum: Hardware
- Topic: ESP32-WROOM-32D high current consumption while asleep
- Replies: 0
- Views: 58
- Tue Jul 30, 2024 8:16 am
- Forum: ESP32 Arduino
- Topic: Bewst way to monitr a coin battery
- Replies: 8
- Views: 3316
Re: Bewst way to monitr a coin battery
Well,
Actually my issue is that one but at another level i have a similar problem with the board's sensor terminals.
Here is the design
Screenshot from 2024-07-30 17-03-42.png
Because GPIO 32 qnd 33 can be used for digital and analog inputs, i added the 2N7002 so i can connect sensors that are ...
Actually my issue is that one but at another level i have a similar problem with the board's sensor terminals.
Here is the design
Screenshot from 2024-07-30 17-03-42.png
Because GPIO 32 qnd 33 can be used for digital and analog inputs, i added the 2N7002 so i can connect sensors that are ...
- Tue Jul 30, 2024 6:45 am
- Forum: ESP32 Arduino
- Topic: Bewst way to monitr a coin battery
- Replies: 8
- Views: 3316
Re: Bewst way to monitr a coin battery
Hello,
I read about the attenuation variable when using the ADC. I am just a bit confused. I know that the mac voltage you can apply to a pin is 3.3v, however it seems that there is not really a way to read a voltage higher than 2.45v ? i mean if i apply a voltage of 2.8 to a pin, does that mean ...
I read about the attenuation variable when using the ADC. I am just a bit confused. I know that the mac voltage you can apply to a pin is 3.3v, however it seems that there is not really a way to read a voltage higher than 2.45v ? i mean if i apply a voltage of 2.8 to a pin, does that mean ...
- Mon Jul 29, 2024 8:33 am
- Forum: ESP32 Arduino
- Topic: Bewst way to monitr a coin battery
- Replies: 8
- Views: 3316
Re: Bewst way to monitr a coin battery
Hello,
Actually the original reason i started this thread is because i made a board where i connected the battery + directly to the ADC pin. The problem is that when the board was not energized the rtc battery would be drained in less than 2 days.
So that is why i thought of a resistor or a divider ...
Actually the original reason i started this thread is because i made a board where i connected the battery + directly to the ADC pin. The problem is that when the board was not energized the rtc battery would be drained in less than 2 days.
So that is why i thought of a resistor or a divider ...
- Mon Jul 29, 2024 5:26 am
- Forum: ESP32 Arduino
- Topic: Bewst way to monitr a coin battery
- Replies: 8
- Views: 3316
Re: Bewst way to monitr a coin battery
Thanks for that info.
Just to confirm, I will use only a 2Mohm resistor between the positive of the battery and the GPIO pin. Then when the value of the ADC falls below 2.45V i will flag the battery as needing replacement. Is that correct?
thanks
Just to confirm, I will use only a 2Mohm resistor between the positive of the battery and the GPIO pin. Then when the value of the ADC falls below 2.45V i will flag the battery as needing replacement. Is that correct?
thanks
- Sun Jul 28, 2024 11:49 pm
- Forum: ESP32 Arduino
- Topic: Bewst way to monitr a coin battery
- Replies: 8
- Views: 3316
Bewst way to monitr a coin battery
Hello,
The board i am designing has an rtc chip and a 1220 3v coin battery as bacup power. I want to monitor the battery voltage using anm ADC pin but i am worried about current leakage. I thought of either putting a voltage divider with 2Mohms and 1 Mohm as resistors and connect the pin there, the ...
The board i am designing has an rtc chip and a 1220 3v coin battery as bacup power. I want to monitor the battery voltage using anm ADC pin but i am worried about current leakage. I thought of either putting a voltage divider with 2Mohms and 1 Mohm as resistors and connect the pin there, the ...
- Sun Jul 28, 2024 9:58 am
- Forum: Hardware
- Topic: Choosing resistor values for a voltage divider ESP32-C3 analogue input
- Replies: 3
- Views: 5867
Re: Choosing resistor values for a voltage divider ESP32-C3 analogue input
Hello,
i have a very similar problem. i have an rtc which uses a 1220 battery 3v as backup power.
i want to read the voltage of the battery using an analog pin and to avoid draining the battery when the power is off i thought of connecting the output lf the battery to the pin on the esp32 with a ...
i have a very similar problem. i have an rtc which uses a 1220 battery 3v as backup power.
i want to read the voltage of the battery using an analog pin and to avoid draining the battery when the power is off i thought of connecting the output lf the battery to the pin on the esp32 with a ...