SN74CBTLV3245A: what is the basic output structure of SN74CBTLV3245APWR？Does this switch require an external pull resistor?

hanbo chen

Prodigy 80 points

Part Number: SN74CBTLV3245A

what is the basic output structure of SN74CBTLV3245APWR？Does this switch require an external pull resistor?

over 2 years ago

0 Clemens Ladisch over 2 years ago

Guru 318490 points

This is an analog switch with transmission gates; it does not have any outputs.

When a pin is disconnected, it is floating unless you add a pull-up/-down resistor.

0 hanbo chen over 2 years ago in reply to Clemens Ladisch

Prodigy 80 points

Is the following figure its output structure? Can I add an external pull-up/down resistor to a connected PIN ? Does the external pull-down resistor on the connected pin affect its function?

0 Rami Mooti1 over 2 years ago in reply to hanbo chen

TI__Mastermind 35648 points

Hey hanbo,

yes, this is the internal architecture of the device. For information on the transmission gates we have an FAQ here :

[FAQ] What are the Types of Architectures TI Switches and Multiplexers Use and how do I know which one my device has internally?

Regardless of the architecture, this device, along with all our other analog muxes, act as passive components. So as Clemens mentioned "When a pin is disconnected, it is floating unless you add a pull-up/-down resistor".
So the external pulldown will effect the function of the output of the device, as it will pulldown the output.

Thanks,
Rami

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SN74CBTLV3245A: what is the basic output structure of SN74CBTLV3245APWR？Does this switch require an external pull resistor?