Looked everywhere but can’t find an answer….
Does the Arduino Nano R4 recharge a LIR2032 (rechargeable lithium battery) coin cell connected to VBATT?
I know that DS3231 modules recharge them and I’m hoping the R4 will otherwise I might have to double up on RTCs!
Does anyone here know?
I am using a standard Lithium bag battery. Keep in mind the R4 RTC is VERY inaccurate especially compared to the DS3231.
Not familiar with Nano R4, but check the datasheet for max VBATT. A fully charged LIR2032 is over 4V. I use an ML1220 on my Giga as it has a 3.6V limit and the ML1220 is just over 3V fully charged.
Good to know - thanks, @sonofcy. During my searches I bumped into various issues with the R4 RTC and was hoping they’d all been resolved by now. Apparantly not.
I guess I’ll stick with the DS3231 modules I’ve been using.
You might want to take a look at the "charging" circuit of your DS3231 module. If you have the ZS-042 module, the one with the EEPROM chip on it, then the charging ciruit is a diode and a resistor. If you power the module with 5V at Vcc, the charging voltage will be too high, and charging will never terminate. If you power it with 3.3V, there will be essentially no charging at all because the voltage will be something like 2.8V or less. So I think most people these days disable that charging circuit, and just use a CR2032, which usually lasts years.
No and as @steve9 mentioned an LIR2032 should NOT be used.