Technical Summary: 74164 8-Bit SIPO Shift Register

74164 8-Bit Serial-In Parallel-Out (SIPO) Shift Register

Overview

The M54/74HC164 is a high-speed CMOS 8-bit serial-in parallel-out (SIPO) shift register fabricated using silicon gate C2MOS technology. This component is designed for applications requiring serial-to-parallel data conversion with high-speed operation and low power consumption. The device features two serial data inputs (A and B) that are ANDed together, allowing flexible input configurations. The 74HC164 is part of the 74HC family, ensuring compatibility with other high-speed CMOS logic devices while maintaining the robustness of CMOS technology.

With its advanced C2MOS process, the 74HC164 achieves high-speed performance comparable to LSTTL while consuming significantly less power. The shift register is edge-triggered, responding to low-to-high transitions on the clock input (CP), and includes an asynchronous master reset (MR) to clear all outputs to a low state regardless of the clock or input conditions.

Features

High-Speed Operation: Typical propagation delay of 13 ns at V_CC = 5V
Low Power Consumption: Maximum I_CC of 4 µA at T_A = 25°C
Wide Operating Voltage Range: 2V to 6V, compatible with TTL levels
8-Bit Serial-In Parallel-Out Operation: Converts serial data to parallel output
Dual Serial Data Inputs (A and B): ANDed together for flexible input control
Asynchronous Master Reset (MR): Clears all outputs independently of the clock
Balanced Propagation Delays: Ensures reliable synchronous operation
High Noise Immunity: Standard CMOS noise margin of 0.45 V_CC
Pin and Function Compatible with 74LS164: Drop-in replacement for LSTTL versions

Applications

The 74HC164 is widely used in digital systems where serial-to-parallel data conversion is required. Key application areas include:

Data Serialization: Converting serial data streams to parallel outputs for display drivers or memory interfaces
LED Matrix Control: Driving columns or rows in multiplexed LED displays
Digital Clocks and Counters: Implementing shift register-based timing circuits
Communication Systems: Buffering and processing serial data in UARTs and other interfaces
Industrial Control Systems: Expanding I/O capabilities in microcontroller-based systems
Test and Measurement Equipment: Generating test patterns or capturing serial data

Electrical Characteristics

Absolute Maximum Ratings

Supply Voltage (V_CC): -0.5V to +7V
Input Voltage (V_IN): -0.5V to V_CC + 0.5V
Output Voltage (V_OUT): -0.5V to V_CC + 0.5V
Operating Temperature Range: -55°C to +125°C
Storage Temperature Range: -65°C to +150°C

DC Characteristics (V_CC = 4.5V to 5.5V, T_A = -40°C to +85°C)

High-Level Input Voltage (V_IH): 3.15V min
Low-Level Input Voltage (V_IL): 1.35V max
High-Level Output Voltage (V_OH): 4.4V min (I_OH = -4 mA)
Low-Level Output Voltage (V_OL): 0.1V max (I_OL = 4 mA)
Input Leakage Current (I_IN): ±1 µA max
Quiescent Supply Current (I_CC): 4 µA max

AC Characteristics (V_CC = 5V, T_A = 25°C)

Maximum Clock Frequency (f_max): 50 MHz typical
Propagation Delay (CP to Q_n): 13 ns typical
Setup Time (Data to CP): 20 ns min
Hold Time (Data to CP): 5 ns min
Master Reset Pulse Width (t_w): 25 ns min

Package Information

The 74HC164 is available in multiple package options to suit different application requirements:

14-Pin Packages

SO-14: Small Outline Package (3.9mm × 8.65mm)
TSSOP-14: Thin Shrink Small Outline Package (5mm × 4.4mm)
PDIP-14: Plastic Dual In-Line Package (19.3mm × 6.35mm)

Pin Configuration

The pinout for the 74HC164 is as follows:

Pin 1: Data Input A
Pin 2: Data Input B
Pin 3: Output Q0
Pin 4: Output Q1
Pin 5: Output Q2
Pin 6: Output Q3
Pin 7: Ground (GND)
Pin 8: Clock Input (CP)
Pin 9: Master Reset (MR, active low)
Pin 10: Output Q4
Pin 11: Output Q5
Pin 12: Output Q6
Pin 13: Output Q7
Pin 14: Supply Voltage (V_CC)

Functional Description

The 74HC164 operates as a positive-edge-triggered shift register. Data is entered serially through the AND combination of inputs A and B (i.e., the effective data input is A·B). On each low-to-high transition of the clock input (CP), the data at the serial input is shifted into the first stage (Q0), with each subsequent stage receiving the data from the previous stage. All eight output stages are accessible simultaneously, providing parallel output capability.

The master reset input (MR), when held low, asynchronously clears all outputs to low regardless of the clock or data inputs. This feature provides immediate initialization capability when needed. When MR is high, normal shifting operation proceeds on clock edges.