The ST2129 is a 2-bit dual supply level translator from ST, which provides the level shifting capability to allow data transfer in a multi-voltage system. Externally applied voltages, VCC and VL, set the logic levels on either side of the device. Its architecture allows bidirectional level translation without a control pin. The ST2129 accepts VL from 1.65 to 3.6 V and VCC from 1.65 to 5.5 V, making it ideal for data transfer between low-voltage ASICs/PLD and higher voltage systems. This device has a tri-state output mode which can be used to disable all I/Os. When VCC is grounded/floating or when the device is disabled via the OE pin, the ST2129 supports power-down mode.