BQ25703A: SCLK Pulse Width Low

S.Satoshi

Part Number: BQ25703A

Hi,

The tw(L) is specified as 4.7us(min) in datasheet and I think that it should be for 100kHz clock frequency. And so it should be 1.3us(min) for 400kHz clock frequency. Is my understanding correct?

Best Regards,

Satoshi

over 5 years ago

0 Joel Hernandez II over 5 years ago

TI__Mastermind 25800 points

Hey Satoshi,

1.3us is specified in the I2C specification for the minimum LOW period of the SCLK line in Fast Mode (up to 400kHz).

The specification in our datasheet meets this requirement as we providing at least 4.7us of LOW period, which is greater than the minimum of 1.3us defined in the I2C specification.

As a technicality, it should a minimum of 1.3us, but the Standard Mode specification for this parameter encompasses the Fast Mode specification.

Regards,

Joel H

0 S.Satoshi over 5 years ago in reply to Joel Hernandez II

Guru 21685 points

Hi Joel,

Thank you for your comment. But I don't think 4.7us(min) encompasses Fast Mode specification, 400kHz. The duration of low period at 400kHz is less than 2.5us, so it violate 4.7us min spec.

The attached example is referred from gauge IC. I think this should be correct description.

Best Regards,

Satoshi

0 Joel Hernandez II over 5 years ago in reply to S.Satoshi

TI__Mastermind 25800 points

Hey Satoshi,

Understood. I believe this specification should provide the test condition of 100kHz SCL clock frequency.

I will speak with my system's team on this specification.

Regards,

Joel H

0 S.Satoshi over 5 years ago in reply to Joel Hernandez II

Guru 21685 points

Hi Joel,

Thank you for your understanding. I'm waiting for your update.

Best Regards,

Satoshi

0 Joel Hernandez II over 5 years ago in reply to S.Satoshi

TI__Mastermind 25800 points

Hey Satoshi,

The charger does support the 400kHz (Fast Mode) I2C operation.

However, the specification is not clear and only represents the 100kHz timing specification.

We will clarify this in a future revision of the datasheet.

Regards,

Joel H

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BQ25703A: SCLK Pulse Width Low