CD54HCT138 Overview
Description
The CDx4HC(T)138 and '238 are three to eight decoders with one standard output strobe (G2) and two active low output strobes (G 1 and G 0). When the outputs are gated by any of the strobe inputs, they are all forced into the high state.
Key Features
- Select one of eight data outputs: – Active low for '138 – Active high for '238
- l/O port or memory selector
- Three enable inputs to simplify cascading
- Typical propagation delay of 13 ns at VCC = 5 V, CL = 15 pF, TA = 25°C
- Fanout (over temperature range) – Bus driver outputs: 15 LSTTL loads – Standard outputs: 10 LSTTL loads
- Wide operating temp range: -55°C to 125°C
- Balanced propagation delay and transition times
- Significant power reduction compared to LSTTL logic ICs
- HC types – 2 V to 6 V operation – High noise immunity: NIL = 30%, NIH = 30% of VCC at VCC = 5 V
