BQ27Z561-R1: I2C pull-up resistor

Miranda Gu

Part Number: BQ27Z561-R1

Hi team,

May I know the minimum resistance value of BQ27Z561-R1 I2C pull-up resistors?

Customer want to use 1kohm to decrease power loss. Baud rate is 400kHz and voltage is 1.8V. Could you give some comments?

Thanks,

Miranda

over 6 years ago

0 Onyx Ahiakwo over 6 years ago

TI__Guru* 76230 points

hi Miranda

The external pull-up devices connected to the bus lines must be adapted to accommodate the shorter maximum permissible rise time for the I2C-bus. pls see the i2c spec and data sheet of the device for the rise times.

I have attached an app no on sizing the resistor of i2 c devices.0841.calculating the pull_ups for i2c lines.pdf

thanks

Onyx

0 Miranda Gu over 6 years ago in reply to Onyx Ahiakwo

TI__Genius 16632 points

Hello Onyx,

What is the value of Cb and IOL? I cannot find them in datasheet.

Thanks,

Miranda

Power management

Power management forum

BQ27Z561-R1: I2C pull-up resistor