TI level-translation devices offer an opportunity for successful mixed-voltage signal design. A proper power-up sequence must always be followed to avoid excessive supply current, bus contention, oscillations, or other anomalies caused by improperly biased device pins. Take these precautions to guard against such power-up problems:

1. Connect ground before any supply voltage is applied.
2. Power up the control side of the device (V_CCA for all four of these devices).
3. Tie OE to V_CCA with a pullup resistor so that it ramps with V_CCA.
4. Depending on the direction of the data path, DIR can be high or low. If DIR high is needed (A data to B bus), ramp it with V_CCA. Otherwise, keep DIR low.

For more information, see the TI application report, Texas Instruments Voltage-Level-Translation Devices (SCEA021).