I've built the circuit for a 6S 3.7V battery management system (BMS) using a BQ7693003 and Arduino Nano. However, I'm encountering communication issues between the Arduino and the chip. Here's my schematic :
You need to connect the Nano to the BMS chip. The communications issues are due to this non-connection.
Please don't say that you have, I can see from your schematic that you haven't.
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Iam sorry for not including the schematic, sir. I don't design it on software. so, here's the picture of the connection between bq7693003 and nano
And when the micro is connected, remember to carry the ground across all components.
I apologize for that. I've changed the category, thank you for your advice.
I have connected the ground of all components, sir. Do i have to connect the cells to check the communication, sir?
here's my i2c scanner code :
#include <Arduino.h>
#include <Wire.h>
void setup()
{
Wire.begin(); // Initialize I2C bus with default pins
Serial.begin(9600);
while (!Serial); // Leonardo: wait for serial monitor
Serial.println("\nI2C Scanner");
}
void loop()
{
byte error, address;
int nDevices;
Serial.println("Scanning...");
nDevices = 0;
for(address = 1; address < 127; address++ )
{
// The i2c_scanner uses the return value of
// the Write.endTransmission to see if
// a device did acknowledge to the address.
Wire.beginTransmission(address);
error = Wire.endTransmission();
if (error == 0)
{
Serial.print("I2C device found at address 0x");
if (address < 16)
Serial.print("0");
Serial.print(address, HEX);
Serial.println(" !");
nDevices++;
}
else if (error == 4)
{
Serial.print("Unknown error at address 0x");
if (address < 16)
Serial.print("0");
Serial.println(address, HEX);
}
}
if (nDevices == 0)
Serial.println("No I2C devices found\n");
else
Serial.println("done\n");
delay(5000); // wait 5 seconds for next scan
}
i get it from chatGPT
i apologize, i forget to include i2c scanner that i got from chatGPT
#include <Arduino.h>
#include <Wire.h>
void setup()
{
Wire.begin(); // Initialize I2C bus with default pins
Serial.begin(9600);
while (!Serial); // Leonardo: wait for serial monitor
Serial.println("\nI2C Scanner");
}
void loop()
{
byte error, address;
int nDevices;
Serial.println("Scanning...");
nDevices = 0;
for(address = 1; address < 127; address++ )
{
// The i2c_scanner uses the return value of
// the Write.endTransmission to see if
// a device did acknowledge to the address.
Wire.beginTransmission(address);
error = Wire.endTransmission();
if (error == 0)
{
Serial.print("I2C device found at address 0x");
if (address < 16)
Serial.print("0");
Serial.print(address, HEX);
Serial.println(" !");
nDevices++;
}
else if (error == 4)
{
Serial.print("Unknown error at address 0x");
if (address < 16)
Serial.print("0");
Serial.println(address, HEX);
}
}
if (nDevices == 0)
Serial.println("No I2C devices found\n");
else
Serial.println("done\n");
delay(5000); // wait 5 seconds for next scan
}
Your Mileage May Vary.
I see Vcc, SDA, SCL, REGOUT. I don't see....
Hi, @weha_rosyid34
You have Regout connected to Vin, this is not connected to the 5V of the Nano.
Vss is connected to gnd, correct.
Sda and Sdl appear correct.
What does the Regout OUTPUT from the BMS do, and why is it connected to the Nano Vin, power supply input pin?
Tom.. 
BQ76920.PDF (1.4 MB)
1 Like
Thank you for your response. I use hole pcb, so it looks so messy, but iam sure i've connected all the gnd, sir
ohh i see. thank you for the answer, tom. so how do i powering bq76930? i've tried to supply BAT and other pins. but it still didn't powered the chip
RegOut is an OUTPUT from the IC.
RESRC is the Input, if you read the pin table.
Can you please post a copy of your circuit, a picture of a hand drawn circuit in jpg, png?
Hand drawn and photographed is perfectly acceptable.
Please include ALL hardware, power supplies, component names and pin labels.
Because the schematic you have supplied is Ti recommended circuit.
NOW reverse engineer your project and draw a schematic of YOUR project.
Can you please post some images of you project?
So we can see your component layout.
Can you please tell us your electronics, programming, arduino, hardware experience?
Do you have a DMM? (Digital MultiMeter)
Thanks.. Tom..
Thank you so much, Tom. Here is my schematic. But iam not done yet with the program and check the hardware. because i stuck on communicating arduino and bq76930.
bq769x0 BMS Configurations for Cordless Appliances-5-8.pdf (483.7 KB)
here is my refference by the way