SN74HC164NSR

Logic - Shift Registers

The SN74HC164NSR belongs to the family of logic shift registers and is a serial-input/parallel-output shift register. It is ideal for applications requiring conversion of serial data to parallel data. The SN74HC164NSR contains an 8-stage serial shift register and an 8-bit storage register. Data is shifted on a positive logic transition at the shift register clock input (SHCP). The output data is available from the storage register stage outputs after each positive clock transition at the storage register (STCP). This serial shift-register is designed for high-speed operation and has a clock frequency of 25MHz.

Application Field

The SN74HC164NSR is versatile and can be used for a wide range of application fields that require serial-to-parallel conversion. These fields are:

• Communication systems
• Displays
• Computer systems
• Robotics
• Instrumentation
• Data acquisition systems

Working Principle

The SN74HC164NSR is a serial-to-parallel converter that works on the principle of shift registers. It contains an 8-stage serial shift register and an 8-bit storage register. The serial data is shifted in the shift register once a positive logic transition is present at the SHCP (shift register clock input). This data is available at the storage register (STCP) for parallel output after each positive clock transition. The output data is available from the storage register stage outputs. The data stored in this shift register is maintained until new data is loaded from the data input line.

The SN74HC164NSR has an internal master reset function which initializes the shift register to its all zero state, regardless of the logic level of the data inputs. When the master reset is low, the current data in the shift is retained, but the data is shifted on each clock transition. This feature is useful for applications that require multiple-word shifting.

The SN74HC164NSR has an additional asynchronous reset (RST) pin that enables the user to initialize the contents of the shift register independently of the logic levels of the data input or clock input pins. When the RST pin is low, the current data in the shift register is retained, but the data is shifted on each clock transition.

The Reset input operates in conjunction with the Serial-Input and clock pin. When the Reset input is activated the data in the shift register is cleared and all outputs are driven low, regardless of the Serial-Input or clock pin. The Reset input must be enabled after all of the inputs are valid and must remain active until the data is shifted out. The Reset input must then be deactivated prior to the next data input.

Overall, the SN74HC164NSR is a logic IC that allows serial-to-parallel conversion. It is ideal for a wide range of application fields such as communication systems, displays, computer systems, robotics, instrumentation, and data acquisition systems. Its high-speed operation and internal reset function makes it a perfect choice for applications requiring simple and reliable conversion.