The U74HC595AG-S16-R is a high-speed CMOS 8-bit serial-in, serial or parallel-out shift register featuring an output latch and 3-state (tri-state) outputs. It is manufactured by Unisonic Technologies (UTC). This integrated circuit (IC) is widely implemented to expand the available digital output pins on microcontrollers. [1, 2, 3, 4, 5]
Part Number Breakdown
- U74HC: High-speed CMOS logic family.
- 595: 8-bit shift register with storage register configuration.
- A: Specific design revision or modification variant.
- G: Halogen-free and RoHS-compliant material composition.
- S16: Housed in a standard 16-pin Small Outline Package (SOP-16) surface-mount form factor.
- R: Shipped in Tape & Reel packaging format for automated assembly. [1, 2, 3, 5]
Key Specifications
- Operating Voltage Range: \(2\text{V}\) to \(6\text{V}\).
- Output Current Capability: Up to \(35\text{mA}\) per pin.
- Propagation Delay: \(14\text{ns}\) at \(6\text{V}\) with a \(50\text{pF}\) load.
- Power Dissipation (\(P_{d}\)): Maximum \(500\text{mW}\).
- Operating Temperature Range: \(-40^{\circ }\text{C}\) to \(+125^{\circ }\text{C}\). [1]
Functionality
The IC accepts data serially through the serial input pin (SER). The internal shift register advances data on the low-to-high transition of the shift clock (SRCLK). Data transfers to the storage register on a low-to-high transition of the latch clock (RCLK). The 3-state parallel outputs (\(Q_{0}\)–\(Q_{7}\)) can drive high-current loads directly, such as LED arrays or multiplexed displays. A dedicated serial output pin (\(Q_H’\)) enables cascaded, multi-chip expansion arrangements.

