TCA9406

SCPS221 – JULY 2010

www.ti.com

PRINCIPLES OF OPERATION

Application Notes

The TCA9406 A-Port I/O has open-drain outputs with an internal 10-k

has an internal 10-k

disabled for power saving caused by pullup resistors.

Figure 1. Typical Design Example

connected, and the connected external system is still powered own, the system can be put into standby mode by

shutting down the power rail. In this state, the TCA6406 has a leakage current of approximately 2 µA caused by

current flow from powered-on system.

Power Up, Power Down

One advantage of the TCA9406 translator is that either power supply can be ramped up first. Another advantage

is that either power supply can be set to 0 V, and the outputs are in high-impedance state.

The recommended power up sequence is:

2. Drive the OE input high to enable the device

The recommended power down sequence is:

1. Drive OE input low to disable the device

Enable/Disable

The TCA9406 han an OE input that is used to disable the device by setting OE low, which place all I/Os in the

should be used to ensure that bus contention, excessive currents, or oscillations do not occur during power up

and power down. The value of resistor is based upon the current sinking capability of the device.

10

Submit Documentation Feedback

Copyright © 2010, Texas Instruments Incorporated

Product Folder Link(s): TCA9406