Go Down

Topic: Trouble setting up I2C Battery Monitor with Arudino (Read 115 times) previous topic - next topic

noneused

Hello, I am trying to use an I2C battery monitor on an Arduino UNO powered by an external Li+ battery pack. The part is a Maxim DS2745, and this is the data sheet: https://datasheets.maximintegrated.com/en/ds/DS2745.pdf

I am familiar with how I2C works but I'm having trouble understanding the connections and the pins of the chip. Here is my thinking:

SCL & SDA pins ---> connect to SCL & SDA pins on Arduino
*This is about as much as I'm sure of. The rest is guess work*

PIO -> Unused
SNS->To negative terminal of battery through a resistor and Vss
Vss-> To negative terminal of battery.
CTG-> To Arduino ground
VIN-> To Arduino VIN(???)
Vdd->To positive battery terminal(???)

As you can tell I'm really unsure of which power/ground pins go where according to the data sheet. I'm also confused as tot he Vdd pin connecting to the positive battery terminal through a decoupling terminal. If anyone has used this chip or a similar one before I would love some insight into what I'm looking at wrong. Thank you for any comments or help!


chucktodd

Hello, I am trying to use an I2C battery monitor on an Arduino UNO powered by an external Li+ battery pack. The part is a Maxim DS2745, and this is the data sheet: https://datasheets.maximintegrated.com/en/ds/DS2745.pdf

VIN-> To Arduino VIN(???)
Vdd->To positive battery terminal(???)


You CANNOT connect the positive terminal of the battery to VIN of the Arduino.  This circuit IS NOT a charge controller.  It is just a monitor circuit.

You need a Charge controller.

Look at figure 3.  Page 6 of the data sheet.  the Pack + and Pack - are where the charge controller connects.

Chuck.
Currently built mega http server, Now converting it to ESP32.

noneused

Hey Chuck, appreciate the reply. I was having trouble understanding what the Pack + and - were, thanks for the clarification. With your clarification I'm better able to understand the schematic.

Go Up