The TC74HC165A is a high-speed 8-bit parallel-load shift register fabricated with silicon gate CMOS technology. This device operates in either serial or parallel data entry modes. When the Shift/Load (SH/̄LD) input is low, parallel data is loaded synchronously into the register. When SH/̄LD is high, data is shifted serially into the first flip-flop on the positive-going clock transition. Serial data enters via the Serial Data (DS) input.

Applications

• Keyboard scanning
• Multiplexed displays
• Remote control systems
• Data acquisition systems
• General-purpose logic circuits

Features

• High Speed: tpd = 14 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(opr) = 2 V to 6 V

Benefits

• High-speed operation enables quick data transfer in demanding applications.
• Low power consumption is ideal for battery-operated devices and energy-conscious systems.
• High noise immunity ensures reliable performance in noisy industrial environments.
• Strong output drive capability allows the device to interface directly with other logic families.
• Symmetrical output impedance improves signal integrity.
• The ability to load data in parallel or serially provides design flexibility.

Additional Details

The TC74HC165A has a clock inhibit function that allows the clock signal to be stopped without affecting the data in the register. The complement of the last stage (QH) is also available as an output. This register is particularly useful in applications where parallel data must be converted to serial format. The device uses a standard pinout and is easy to interface with other TTL and CMOS logic.

The TC74HC165A is available in various package types, including DIP16 and SO16, and operates over a temperature range suitable for industrial and commercial applications. Consult the datasheet for specific package and temperature ratings.