• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 65 subscribers
  • Views 1026 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ27541 HDQ Interface issue...

Charles H
Intellectual 895 points
Other Parts Discussed in Thread: BQ27541-V200, BQ27541

I’m very interested in the TI Battery Gauge bq27541-V200.

This part supports both I2C (2-wire) and HDQ interface (1-wire). From the datasheet “The bq27541 is shipped in the I2C mode. TI provides tools to enable the HDQ peripheral.” How do you get this part into HDQ mode? We will NOT have access to an I2C interface. How do we get the part to respond over the HDQ interface? Once configured for HDQ interface, does the device remain in HDQ interface during power-cycles

  • 0
    TI__Genius 14985 points

    You should design I2C test points on your PCB and then use I2C for programming your golden dataflash file into the bq27541-V200.  At the end of pack production, you would send the series of commands and power cycle the PCB to convert it to HDQ mode.  This is a one-way process and sets some non-volatile bits so that it will be stuck in HDQ from that point forward.  HDQ is extremely slow and not suited for programming the flash in production.

  • 0 in reply to dMax
    Intellectual 430 points

    What exactly is the process? For test purposes, I have an MSP430 with HDQ and/or I2C code (from TI)  for the BQ27541. Is there MSP430 code available for the conversion to HDQ, or can you give us the I2C sequence?

    You say, "extremely slow and not suited"... but for prototyping and experimentation, will it work?

    Even if it is slow, it's a shame there's not an HDQ-line sequence that will shift from I2C to HDQ,  and allow production the ability to program through the HDQ interface. It means I have to touch the board before the battery is assembled, even though the interface comes out to the battery connector.

  • 0 in reply to Mike Kaelin
    Prodigy 10 points

    I hope this helps even though late (maybe save the next guy a few minutes). The I2C commands are the addresses to read with HDQ. LSB/MSB. I.E. read address 0x08 for LSB and 0x09 for MSB of Voltage.