SN74LV1T125: State of buffer output with no power supply

Viggo Joergensen

Prodigy 160 points

Part Number: SN74LV1T125
Other Parts Discussed in Thread: SN74LVC1T45, SN74AXC1T45

Hi,

what is the state of the output Y when

nOE = 0V ie output is enabled

VCC = 0V

A = X

best regards

Viggo

over 6 years ago

0 ShreyasRao over 6 years ago

TI__Guru 62160 points

Viggo,

With the device power supply at 0V, the Y will be 0. However, note that this device doesn't support Ioff, and hence external signal on Y is not recommended during this time.

0 Viggo Joergensen over 6 years ago in reply to ShreyasRao

Prodigy 160 points

thank you Shreyas,

ok, I have a CPU TX pin connnected to a Bluetooth RX pin through a SN74LV1T125.

When the Bluetooth module and the SN74LV1T125 is povered off, the CPU TX will not keep the Bluetooth halfe alive.

Right ?

Regards

Viggo

0 ShreyasRao over 6 years ago in reply to Viggo Joergensen

TI__Guru 62160 points

Viggo,

The SN74LV1T125 will not accidently turn on the bluetooth device since the input is Overvoltage tolerant.
What are the voltage levels during normal operation?
You could also consider using the SN74AXC1T45 or the SN74LVC1T45 which supports Ioff partial power down mode to ensure Hi-Z during Vcc power down.

Logic

Logic forum

SN74LV1T125: State of buffer output with no power supply