BQ34Z100EVM: LED interface

Connor Connaughton

Part Number: BQ34Z100EVM

Hello,

From the 34z100 when the single LED interface is being driven, is P1 actively driven both high and low during its 1Hz PWM ?

They shown a pull down on the EVM.

Thanks,

Connor

over 2 years ago

+1 Steven Yao over 2 years ago

TI__Genius 12215 points

Connor Connaughton

In the EVM schematic, the LED signal from P1 drives a NFET to control the LED, thus the high potential on this pin would turn on the NFET and get the LED lit on

0 Connor Connaughton over 2 years ago

TI__Expert 4470 points

Thanks Steven.

Just to confirm, It is true that P1 always drives its line as an output both high and low when used in the single LED mode?

0 Steven Yao over 2 years ago in reply to Connor Connaughton

TI__Genius 12215 points

Connor Connaughton

Are you asking if the external pull up or low is needed for this pin, per the schematic of EVM, external pull up or down is not necessary for this pin

0 Connor Connaughton over 2 years ago

TI__Expert 4470 points

Hi Steven,

Yes that is closer to what I am trying to get answered.

What does the internal structure of the pin looks like? Is it an open-drain or is it a push-pull? Based on your response, it seems you’re implying the pin structure is a push-pull.

+1 Steven Yao over 2 years ago in reply to Connor Connaughton

TI__Genius 12215 points

Connor Connaughton

According to the data sheet, this pin is not an IOD pin, i.e., an open drain output pin, it is a general purpose IO pin, so it is a push pull structure.

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BQ34Z100EVM: LED interface