BQ40Z50-R2: SMBus T_timeout

Zhihan Zhang

Part Number: BQ40Z50-R2
Other Parts Discussed in Thread: BQ29312, BQ20Z80, , BQ40Z50

Hi TI Team,

I'm using bq40z50-r2 to replace bq20z80+bq29312. In dataflash, I found in 20z80+29312, there is a NCSMB bit in Operation Cfg B. I'm wondering if in 40z50, there is a same or similar bit?

I found in 40z50, BTL1 & BTL0 of SBS Configuration seems similar. However BTL1,0 have much longer time (e.g. 2s default). So is BTL1,0 same thing as NCSMB in 20z80?

Thanks,

Zhihan

over 4 years ago

0 Wyatt Keller over 4 years ago

TI__Guru** 105760 points

Hello Zhihan,

Yes those are equivalent operations for both gauges, the bq40z50 just gives more options.

Sincerely,

Wyatt Keller

0 Zhihan Zhang over 4 years ago in reply to Wyatt Keller

Expert 1100 points

Hi Wyatt Keller,

Thanks for the explain!

For NCSMB in 20z80, only two options are available: normal (default) and extended. While for 40z50, four are available: 0s, 1s, 2s (default) and 3s. So I assume 2s in 40z50 is equivalent to normal in 20z80? Please advise.

Also in SMBus v1.1 spec, there is a T_timeout seems related to NCSMB or BTL1,0. However, in SMBus spec, T_timeout is limited within 25 ~ 35ms, which seems different from 2s with BTL1,0 = 0x10. Can you please explain the difference?

Thanks,

Zhihan

0 Kang Kang over 4 years ago in reply to Zhihan Zhang

TI__Mastermind 24870 points

Hello Zhihan,

I would abide by the datasheet instead of the smbus specification to be safe.

Thanks!

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BQ40Z50-R2: SMBus T_timeout