BQ25121: High Z, CD and I2C

Dima S

Part Number: BQ25121

Changing CD pin to low and activating HighZ mode.

Will this shutdown I2C?

If i pull CD to low in the middle of an I2C operation, will it cause a failure?

High Impedance mode is the lowest quiescent current state while operating from the battery. During Hi-Z mode
the SYS output is powered by BAT, the MR input is active, and the LSCTRL input is active. All other circuits are
in a low power or sleep state

what are "all other circuits"?

thanks

over 6 years ago

0 ezhao over 6 years ago

TI__Genius 10240 points

Dima,

In Hi-Z mode, all other circuits refer to the circuit from input for charging such as Q1/Q2 and thermistor network etc. excluding the circuits such as for battery to power SYS, the MR input and the LSCTRL input.

0 Dima S over 6 years ago in reply to ezhao

Prodigy 220 points

Thanks,

what about I2C, should this mode effect it?

0 Gautham over 6 years ago in reply to Dima S

TI__Genius 12485 points

Dima,

lowering /CD pin during an I2C communication is not recommended. the device will go to a low power mode when /CD pin is low.

On the bus, it will return in high impedance state.

regards,
gautham

Power management

Power management forum

BQ25121: High Z, CD and I2C