Overview
The CD74HC595DWR is an 8-bit serial-in, parallel-out shift register with 3-state output registers, manufactured by Texas Instruments. This device is part of the HC (High-Speed CMOS) logic family and is designed for a wide range of digital logic applications. It features a serial input and parallel output configuration, making it ideal for expanding the output ports of microcontrollers or other digital systems. The device includes separate clocks for the shift and storage registers, allowing for flexible data transfer and storage operations.
Key Specifications
| Parameter | Min | Max | Unit | Conditions | |
|---|---|---|---|---|---|
| VCC Supply Voltage | -0.5 | 7 | V | ||
| Operating Voltage Range | 2 | 6 | V | ||
| Input Clamp Current (IIK) | ±20 mA | VI < 0 or VI > VCC | |||
| Output Drive at 5 V | ±6 mA | mA | |||
| Low Input Current | 1 µA | µA | |||
| Propagation Delay (tpd) | 14 ns | ns | |||
| Clock Frequency | 4.2 MHz | 36 MHz | MHz | VCC = 2 V to 6 V | |
| Power Consumption (ICC) | 80 µA | 160 µA | µA | VI = VCC or 0, IO = 0 |
Key Features
- 8-bit serial-in, parallel-out shift register with 3-state output registers
- Wide operating voltage range of 2 V to 6 V
- High-current 3-state outputs can drive up to 15 LSTTL loads
- Low power consumption with a maximum ICC of 80 µA
- Typical propagation delay of 14 ns
- ±6-mA output drive at 5 V
- Low input current of 1 µA max
- Direct overriding clear (SRCLR) input, serial (SER) input, and serial output for cascading
- Separate clocks for both the shift and storage registers
- Output-enable (OE) input to control output state
Applications
- Expanding the output ports of microcontrollers or other digital systems
- Display drivers for LED displays, LCD displays, or other display technologies
- Data transfer and storage in digital logic circuits
- Cascading multiple shift registers to increase the number of output bits
- General-purpose digital logic applications requiring serial-to-parallel data conversion
Q & A
- What is the operating voltage range of the CD74HC595DWR?
The operating voltage range is from 2 V to 6 V.
- How many bits does the CD74HC595DWR shift register have?
The CD74HC595DWR has an 8-bit serial-in, parallel-out shift register.
- What is the maximum output drive current at 5 V?
The maximum output drive current at 5 V is ±6 mA.
- Does the CD74HC595DWR have separate clocks for the shift and storage registers?
- How is the output state controlled in the CD74HC595DWR?
The output state is controlled by the output-enable (OE) input.
- What is the typical propagation delay of the CD74HC595DWR?
The typical propagation delay is 14 ns.
- Can the CD74HC595DWR be cascaded with other shift registers?
- What is the maximum power consumption of the CD74HC595DWR?
The maximum power consumption (ICC) is 160 µA.
- What is the purpose of the SRCLR input in the CD74HC595DWR?
The SRCLR input is used for direct overriding clear of the shift register.
- What are some common applications of the CD74HC595DWR?
Common applications include expanding microcontroller output ports, display drivers, and general-purpose digital logic circuits.
