74HC595D Toshiba Semiconductor | Specification, Inventory, Distributors and Datasheet

The 74HC595D is an 8-bit serial-in, parallel-out shift register with output latches and is part of the 74HC (High-speed CMOS) logic family from Toshiba Semiconductor. This device is primarily used for expanding the number of output pins in a digital circuit, allowing for easy control of multiple devices such as LEDs, motors, or other digital peripherals. The 74HC595D is commonly utilized in microcontroller-based projects where controlling a large number of outputs with fewer I/O pins is necessary, making it highly suitable for a variety of embedded applications.

## Key Specifications:

1. Device Type:

* Shift Register: 8-bit serial-in, parallel-out shift register.
* Output Type: Latched outputs that are capable of sourcing or sinking current to control external devices like LEDs.
* Family: High-speed CMOS (HC) logic family.

2. Supply Voltage:

* Operating Voltage Range: The device operates between 2V and 6V, with a typical operating voltage of 5V.
* Vcc: Power supply voltage, typically 5V in most applications.

3. Data Handling:

* Serial Input: Data is input to the 74HC595D serially (one bit at a time) through a single data pin, allowing for efficient use of limited I/O pins.
* Data Output: The data is shifted into an internal shift register and then latched into the output register, providing a parallel output of the shifted bits.
* Clock Inputs:

* Shift Register Clock (SH\_CP): The clock pin that shifts data into the register on each rising edge.
* Latch Clock (ST\_CP): The latch clock pin that transfers data from the shift register to the output register on the rising edge.
* Output Enable (OE): A pin used to disable the outputs when low (for three-state operation).

4. Output Characteristics:

* Output Pins: 8 parallel output pins, each capable of driving up to 6mA (sourcing) or sinking up to 6mA.
* High-Level Output Voltage (VOH): Typically 3.5V at 3.5mA (for Vcc = 5V).
* Low-Level Output Voltage (VOL): Typically 0.25V at 6mA (for Vcc = 5V).
* Output Impedance: The output impedance is suitable for driving small loads like LEDs, small motors, or other logic inputs.

5. Control Pins:

* Shift Register Clock (SH\_CP): Controls the shifting of data into the shift register.
* Storage Register Clock (ST\_CP): Controls the latching of the shifted data into the output registers.
* Serial Data Input (DS): The pin through which serial data is input into the shift register.
* Output Enable (OE): When this pin is low, it enables the output pins. When high, the outputs are in a high-impedance (tri-state) condition, effectively disconnected from the circuit.

6. Temperature Range:

* Operating Temperature: Typically from -40°C to +85°C, which makes the 74HC595D suitable for a wide range of applications, including industrial and automotive systems.
* Storage Temperature: -65°C to +150°C.

7. Package Type:

* The 74HC595D is typically available in a DIP-16 package or SOIC-16 package, offering 16 pins.
* The pinout is standard for CMOS logic devices, and it’s designed for both through-hole and surface-mount applications.

8. Shift Register Functionality:

* The shift register is capable of storing 8 bits of data (1 byte) and transferring it to the parallel output pins upon the activation of the latch clock.
* This enables the device to act as a serial-to-parallel converter, making it ideal for situations where you need to control multiple devices from a single microcontroller I/O pin.

9. Current Consumption:

* Typical Supply Current (Icc): Approximately 4 µA when in static operation.
* The device consumes very little power, especially in standby mode, making it suitable for battery-powered applications.

10. Power Consumption and Efficiency:

* The 74HC595D operates with low power consumption, typically drawing around 4mA during operation, and even less in idle states.
* Its CMOS design ensures low quiescent current, making it ideal for use in energy-efficient circuits.

## Functional Features:

1. Serial-to-Parallel Data Conversion:

* The 74HC595D allows serial data input, with each incoming bit being stored in an 8-bit shift register. Once 8 bits are shifted into the register, they can be transferred to the output pins, enabling parallel data outputs.
* This is useful in situations where microcontrollers or digital systems have limited output pins but need to control multiple devices.

2. Cascade Capabilities (Daisy-chaining):

* The 74HC595D can be cascaded to create wider shift registers by connecting the QH' pin (serial output) of one shift register to the DS pin (serial input) of the next shift register.
* This allows for control of more output devices using fewer microcontroller pins. For instance, you can chain multiple 74HC595D chips to control 16, 24, or even 64 output pins.

3. Latch Functionality:

* Data shifted into the shift register can be latched to the output registers using the storage register clock (ST\_CP), allowing for controlled data timing and enabling synchronous control of multiple devices.
* The latch enables the separation of shifting and latching operations, allowing for non-interfering data handling and control.

4. Three-State Output:

* The output pins can be put into a high-impedance state by setting the OE pin high. This feature is useful when multiple devices need to share the same output lines, as only one device can actively drive the line at a time.

5. Sourcing and Sinking Capability:

* The outputs of the 74HC595D are capable of sourcing or sinking current, making it possible to control both active-low and active-high devices, such as LEDs, relays, and other digital peripherals.

## Applications:

1. LED Control:

* The 74HC595D is commonly used in controlling multiple LEDs. By daisy-chaining multiple shift registers, a single microcontroller can control hundreds of LEDs in a matrix configuration.

2. Relay Control:

* It can be used to control relays for switching larger loads. Cascading multiple 74HC595D devices allows for controlling multiple relay channels using only a few microcontroller pins.

3. Motor Control:

* The shift register can be used to control multiple motors or actuators, particularly in robotics and automation.

4. Data Display:

* It is useful in driving 7-segment displays or other similar types of digital displays. The parallel output allows for efficient driving of each segment.

5. Audio and Video Applications:

* Used for controlling audio equipment, switches, or for applications where parallel control of devices is necessary, such as in multimedia systems.

6. Peripheral Expansion:

* The 74HC595D is ideal for peripheral expansion in digital circuits, where the microcontroller has limited GPIOs but needs to control many devices like switches, LEDs, or other digital outputs.

## Conclusion:

The 74HC595D is a versatile and efficient serial-to-parallel shift register, capable of expanding the output capabilities of a microcontroller or logic circuit. With its simple interface, ability to cascade for expanded control, low power consumption, and wide range of applications, the 74HC595D is a popular choice in embedded systems for managing numerous outputs with minimal microcontroller pin usage. Whether used for controlling LEDs, driving relays, or interfacing with larger systems, this shift register provides an effective solution for many digital control needs.

Q1: What is the Toshiba Semiconductor 74HC595D?
A: The Toshiba 74HC595D is an 8-bit shift register with a serial input and parallel output, commonly used in digital systems for data storage and transfer. It is part of the HC (High-Speed CMOS) family and is often used in applications where data needs to be shifted from serial to parallel formats, such as driving LED displays or controlling multiple devices with a single microcontroller.

Q2: What is the operating voltage range of the 74HC595D?
A: The Toshiba 74HC595D operates within a voltage range of 2V to 6V. This wide range allows it to be used in various digital systems, providing flexibility for both low-voltage and standard voltage applications in consumer electronics, automotive systems, and industrial control.

Q3: What is the maximum clock frequency of the 74HC595D?
A: The Toshiba 74HC595D can operate at a maximum clock frequency of 25 MHz, depending on the supply voltage. This high speed makes it suitable for fast data transfer and timing-critical applications where quick and reliable shifting of data is required.

Q4: How many bits of data can the 74HC595D shift?
A: The Toshiba 74HC595D is an 8-bit shift register, meaning it can shift and store 8 bits of data at a time. This makes it ideal for controlling up to 8 outputs, such as LEDs, motors, or other actuators, using a minimal number of control lines.

Q5: What is the purpose of the shift register in the 74HC595D?
A: The shift register in the Toshiba 74HC595D serves to convert serial data (input one bit at a time) into parallel data (output on multiple pins at once). This allows for efficient use of microcontroller pins by shifting a large amount of data serially and then distributing it to multiple outputs in parallel.

Q6: Does the 74HC595D have a latch function?
A: Yes, the Toshiba 74HC595D has an internal latch. Once the serial data is shifted into the shift register, the latch can be used to hold the data at the output until it is updated with new data, allowing for stable and reliable control of devices.

Q7: What is the power consumption of the 74HC595D?
A: The power consumption of the Toshiba 74HC595D is relatively low, with typical current consumption around 4mA for Vcc = 5V and no load. This makes it suitable for battery-powered applications where energy efficiency is important, such as remote controls or portable devices.

Q8: Can the 74HC595D be used to drive high-current loads directly?
A: No, the Toshiba 74HC595D cannot drive high-current loads directly. Its output pins are capable of sourcing and sinking a maximum of 6mA per pin. For higher current applications, external transistors or MOSFETs are often used to amplify the current to the required level.

Q9: What are the output types of the 74HC595D?
A: The Toshiba 74HC595D features 8 parallel outputs, which are typically in the form of standard digital logic levels. These outputs can drive various devices like LEDs, relays, and displays, provided the current does not exceed the device’s limits.

Q10: How can I cascade multiple 74HC595D shift registers?
A: Multiple Toshiba 74HC595D shift registers can be cascaded by connecting the serial output (QH’ pin) of one shift register to the serial input (DS pin) of the next. This allows for more than 8 output channels by chaining the devices together, making it possible to control hundreds of outputs using just a few control lines.

Q11: Does the 74HC595D support both high and low voltage logic?
A: The Toshiba 74HC595D is compatible with both high and low voltage logic systems, as long as the supply voltage is within its operating range of 2V to 6V. It is designed to work with TTL (Transistor-Transistor Logic) and CMOS (Complementary Metal-Oxide-Semiconductor) logic levels, offering versatility for different circuit designs.

Q12: What are the typical uses of the 74HC595D in electronics?
A: The Toshiba 74HC595D is widely used in applications like LED driving (for controlling multiple LEDs with minimal control pins), shift registers for digital circuits, signal processing, data display systems, and in applications that require control of multiple outputs with a microcontroller, such as in smart home devices and automotive systems.

Q13: What is the maximum operating temperature of the 74HC595D?
A: The Toshiba 74HC595D operates within a temperature range of -40°C to +85°C. This allows it to be used in a variety of environments, including consumer electronics, industrial control systems, and automotive applications where temperature stability is required.

Q14: Can the 74HC595D be used with 3.3V logic systems?
A: Yes, the Toshiba 74HC595D can be used with 3.3V logic systems, but it is important to ensure that the voltage levels are compatible with the device's input thresholds. The 74HC595D is designed to operate with both 3.3V and 5V logic, but the output current capabilities are limited at lower supply voltages.

Q15: How does the 74HC595D handle data when the latch is not updated?
A: When the latch is not updated, the outputs of the Toshiba 74HC595D retain the previous data until the latch pin is activated (latch pulse is received). This ensures that the output values remain stable even if the shift register is still receiving new data.

Q16: How does the 74HC595D handle clock timing?
A: The Toshiba 74HC595D operates with a clock signal (CP pin) that shifts data serially into the shift register. Each rising edge of the clock triggers a shift of the data into the next bit of the shift register. The timing is controlled by the clock pulse, and data is latched into the outputs when the latch pin is activated.

Q17: What is the difference between the 74HC595D and the 74HC165?
A: The key difference between the Toshiba 74HC595D and the 74HC165 is that the 74HC595D is a shift register with a serial input and parallel output, while the 74HC165 is a shift register with parallel input and serial output. This means the 74HC595D is used to drive multiple outputs, while the 74HC165 is used to read multiple inputs sequentially.

Q18: Can the 74HC595D be used in both serial and parallel data transmission?
A: The Toshiba 74HC595D is designed specifically for serial-to-parallel data conversion, which means it accepts data serially and outputs it in parallel. It cannot transmit data in parallel-to-serial format. However, it can receive and store data in serial form and then present it as parallel outputs.

Q19: How can I control the 74HC595D using a microcontroller?
A: The 74HC595D can be controlled by a microcontroller using three control pins: the data pin (DS), clock pin (SH_CP), and latch pin (ST_CP). The microcontroller sends data serially to the shift register, pulses the clock to shift the data, and uses the latch to update the outputs. This allows the microcontroller to control multiple outputs with minimal wiring.

Q20: Can the 74HC595D be used in low-power applications?
A: Yes, the Toshiba 74HC595D is well-suited for low-power applications due to its low current consumption. The power consumption is minimal during operation, making it a good choice for battery-powered devices or systems where energy efficiency is important. However, external drivers may be needed for higher-current applications.