TOSHIBA CMOS Digital Integrated Circuit Silicon Monolithic
8-to-3 Line Priority Encoder
The TC74HC148A is a high speed CMOS 8-to-3 LINE
ENCODER fabricated with silicon gate C2MOS technology.
It achieves the high speed operation similar to equivalent
LSTTL while maintaining the CMOS low power dissipation.
All data inputs and outputs of these encoders are active at the
low logic level.
The encoder detects a low level of the highest order among
eight input signals and outputs the corresponding signal position
in binaly code.
Enable Input EI and Enable Output EO are used to easily
cascade without using external circuits.
All inputs are equipped with protection circuits against static
discharge or transient excess voltage.
• High speed: tpd = 15 ns (typ.) at VCC = 5 V
• Low power dissipation: ICC = 4 μA (max) at Ta = 25°C
• High noise immunity: VNIH = VNIL = 28% VCC (min)
• Output drive capability: 10 LSTTL loads
• Symmetrical output impedance: |IOH| = IOL = 4 mA (min)
• Balanced propagation delays: tpLH ∼− tpHL
• Wide operating voltage range: VCC (opr) = 2 to 6 V
• Pin and function compatible with 74LS148
: 1.00 g (typ.)
: 0.18 g (typ.)
Start of commercial production