The M74HC148 is a high-speed CMOS 8-to-3 line priority encoder fabricated with silicon gate C2MOS technology. It features high speed, low power dissipation, high noise immunity, symmetrical output impedance, etc. The encoder encodes eight data lines to a three-line (4-2-1) binary (octal) format. Cascading circuitry (enable input EI and enable output EO) is provided for octal expansion without the need for external circuitry. The data inputs are active at the low logic level. All inputs are equipped with protection circuits against static discharge and transient excess voltage. The M74HC148 is pin and function compatible with the 74 series 148.