ZHCSAI5C November 2012 – November 2021
PRODUCTION DATA
The BQ27520-G4 fuel gauge supports the standard I2C read, incremental read, quick read, one byte write, and incremental write functions. The 7-bit device address (ADDR) is the most significant 7 bits of the hex address and is fixed as 1010101. The first 8-bits of the I2C protocol is, therefore, 0xAA or 0xAB for write or read, respectively.
Figure 8-3 I2C Read, Incremental Read, Quick Read, One Byte Write, and Incremental Write FunctionsThe “quick read” returns data at the address indicated by the address pointer. The address pointer, a register internal to the I2C communication engine, increments whenever data is acknowledged by the fuel gauge or the I2C master. “Quick writes” function in the same manner and are a convenient means of sending multiple bytes to consecutive command locations (such as two-byte commands that require two bytes of data).
The following command sequences are not supported:
Attempt to write a read-only address (NACK after data sent by master):
Figure 8-4 Invalid WriteAttempt to read an address above 0x6B (NACK command):
Figure 8-5 Invalid Read