SN74LVCH162244A: We want to check the output status before the VCC to the working voltage(<1.65V). Whether it's high impedance?

Frank Xiao

Genius 12055 points

Part Number: SN74LVCH162244A

Hi team,

We want to check the output status before the VCC to the working voltage(<1.65V). Whether it's high impedance? Thanks.

over 3 years ago

0 Clemens Ladisch over 3 years ago

Guru 259500 points

Below 1.65 V, correct operating is not guaranteed, so any output might drive high or low.

To force the I/Os to be high impedance, you must pull OE lowhigh.

0 Dylan Hubbard over 3 years ago in reply to Clemens Ladisch

TI__Mastermind 43480 points

Hey Frank,

Clemens has provided a perfect answer for this, I just wanted to make one slight fix in that the OE pin would need to be pulled high to put the I/O into a high impedance state.

0 Frank Xiao over 3 years ago in reply to Clemens Ladisch

TI__Genius 12055 points

Hi Clemens,

How about the output status if we connect the OE to VCC during VCC below 1.65V? Thanks.

0 Clemens Ladisch over 3 years ago in reply to Frank Xiao

Guru 259500 points

If OE is high (= V_CC), then the outputs are disabled, even during power up.

Logic

Logic forum

SN74LVCH162244A: We want to check the output status before the VCC to the working voltage(<1.65V). Whether it's high impedance?