Features
• Buffered Inputs and Outputs
• Typical Propagation Delay: 12ns at VCC = 5V,
CL = 15pF, TA = 25oC
• Fanout (Over Temperature Range)
- Standard Outputs . . . . . . . . . . . . . . . 10 LSTTL Loads
- Bus Driver Outputs . . . . . . . . . . . . . 15 LSTTL Loads
• Wide Operating Temperature Range . . . -55oC to 125oC
• Balanced Propagation Delay and Transition Times
• Significant Power Reduction Compared to LSTTL
Logic ICs
• HC Types
- 2V to 6V Operation
- High Noise Immunity: NIL = 30%, NIH = 30% of VCC
at VCC = 5V
• HCT Types
- 4.5V to 5.5V Operation
- Direct LSTTL Input Logic Compatibility,
VIL= 0.8V (Max), VIH = 2V (Min)
- CMOS Input Compatibility, Il ≤ 1μA at VOL, VOH

Description
The ’HC42 and CD74HCT42 BCD-to-Decimal Decoders
utilize silicon-gate CMOS technology to achieve operating
speeds similar to LSTTL decoders with the low power
consumption of standard CMOS integrated circuits. These
devices have the capability of driving 10 LSTLL loads and
are compatible with the standard LS logic family. One of ten
outputs (low on select) is selected in accordance with the
BCD input. Non-valid BCD inputs result in none of the
outputs being selected (all outputs are high).