The TC74HC147AF is a high-speed CMOS priority encoder fabricated with silicon gate CMOS technology. It encodes nine data input lines (1-9) to a four-line (A0-A3) BCD output, corresponding to the highest priority input. The device provides a fast and efficient method for prioritizing multiple inputs.

Applications

• Keyboard encoding
• Priority interrupt handling
• Data multiplexing
• Industrial control
• Computer systems

Features

• High-speed operation: tpd = 15 ns (typ.) at VCC = 5V
• 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 = 2 to 6 V
• Encodes nine data input lines to a four-line BCD output

Benefits

• High Speed: Fast encoding allows for quick response in critical systems.
• Low Power Consumption: Minimizes power usage, suitable for battery-operated devices.
• High Noise Immunity: Ensures stable operation in noisy industrial environments.
• Wide Operating Voltage: Compatible with a wide range of power supply voltages.
• Priority Encoding: Simplifies complex interrupt handling and data multiplexing.

Additional Details

The TC74HC147AF is provided in a 16-pin package. When all inputs are high, the output is high. The inputs and outputs are compatible with standard TTL logic levels. This encoder is valuable in applications where multiple inputs need to be prioritized, providing a clear and efficient digital representation of the highest priority input. The device's operating temperature range is -40°C to +85°C.