The HC138/HC238/HCT138/HCT238 are high speed silicon gate CMOS decoders well suited to memory address decoding or data routing applications. The HC138 and HC238 feature low power consumption typically associated with CMOS circuitry, yet have speeds comparable to low power Schottky TTL logic. The HC/HCT138 series has eight normally high outputs, of which, if the device is enabled, these inputs determine which one will go low or which of the normally low outputs of the HC/HCT238 series will go high. Two active low and one active high enables (E1, E2 and E3) are used to simplify cascading.