Part A
74HC594D
Toshiba Semiconductor and Storage
- Lifecycle
- Active
- Stock
- 1976 PCS
- Package
- SOIC-16
- Series
- Lógica - Registos de Maiúsculas
Replacement verdict
Not a drop-in replacement
The 74HC541D and 74HC594D are not functionally interchangeable despite sharing the same 74HC logic family and SOIC-16 package. The 74HC541D is an octal non-inverting buffer/line driver with 3-state outputs, while the 74HC594D is an 8-bit serial-in/parallel-out shift register with output latches. Their internal architectures, pin functions, and control logic differ fundamentally, making direct substitution impossible without circuit redesign.
Different logic function
Different output type
Different pinout
Different control interface
Parts at a glance
Part B
74HC541D
Toshiba Semiconductor and Storage
- Lifecycle
- Active
- Stock
- 5041 PCS
- Package
- SOIC-20
- Series
- Lógica - Buffers, Drivers, Receivers, Transceivers
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | 74HC541D | 74HC594D | Why it matters |
|---|---|---|---|
| Logic Function | Octal buffer/line driver with 3-state outputs | 8-bit serial-in/parallel-out shift register with output latches | The core function determines whether the device buffers signals or performs serial-to-parallel data conversion, making them non-interchangeable in most designs. |
| Output Type | 3-state | Push-pull (registered) | 3-state outputs allow bus sharing, while push-pull latched outputs are intended for driving parallel loads directly. |
| Number of Outputs | 8 | 8 | Both provide eight outputs, but the data path and control scheme differ fundamentally. |
| Data Input Type | Parallel (8 inputs) | Serial (1 input) plus shift register | Parallel inputs pass data combinationally, whereas serial input requires clocking to load data into the shift register. |
| Control Inputs | Output enable (OE1, OE2) | Shift clock, latch clock, output enable, serial clear | Different control schemes affect timing, synchronization, and how the device integrates into a system. |
| Propagation Delay (typical at 5V) | ~10 ns | ~14 ns (clock to output) | Timing differences impact maximum operating frequency and signal integrity in high-speed designs. |
| Supply Voltage Range | 2 V to 6 V | 2 V to 6 V | Both support the standard HC-family supply range, allowing use in 3.3 V and 5 V systems. |
| Package | SO16 (D package) | SO16 (D package) | Identical package and pin count simplify PCB footprint considerations, though pin functions differ. |
| Latch/Register | None | 8-bit shift register with output latch | The presence of storage elements in the 74HC594D enables data retention and synchronized output updates, which the 74HC541D cannot provide. |
| Typical Application | Bus driving, buffering, memory address drivers | LED drivers, I/O expansion, serial-to-parallel conversion | Intended use cases differ significantly, so substitution requires redesigning the interface logic. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 74HC594D | 74HC541D |
|---|---|---|
| Series | 74HC | 74HC |
| Part Status | Active | Active |
| Logic Type | Shift Register | Buffer, Non-Inverting |
| Output Type | Push-Pull | 3-State |
| Number of Elements | 1 | 1 |
| Number of Bits per Element | 8 | 8 |
| Function | Serial to Parallel, Serial | - |
| Voltage - Supply | 2V ~ 6V | 2V ~ 6V |
| Operating Temperature | -40°C ~ 125°C | -40°C ~ 85°C (TA) |
| Mounting Type | Surface Mount | Surface Mount |
| Current - Output High Low | - | 7.8mA, 7.8mA |
Frequently asked questions
What are the primary functional differences between the 74HC541D and the 74HC594D?
The 74HC541D is an octal non-inverting buffer/line driver with 3-state outputs, designed for bus-oriented applications. The 74HC594D is an 8-bit serial-in/parallel-out shift register with output latches, used for serial-to-parallel data conversion and I/O expansion.
Are the 74HC541D and 74HC594D pin-compatible?
No. The 74HC541D and 74HC594D have different pin functions and internal architectures. The 74HC541D provides eight buffer channels with a common output enable, while the 74HC594D provides serial data inputs, shift clock, latch clock, and eight parallel outputs. They are not pin-to-pin replacements.
Can the 74HC541D and 74HC594D be used together in the same design?
Yes. They serve complementary roles. The 74HC594D can convert serial data to parallel outputs, and the 74HC541D can buffer or drive those parallel signals onto a bus or transmission line, provided timing, loading, and voltage-level requirements are respected.
What are the output drive capabilities of the 74HC541D and 74HC594D?
Both devices are members of the 74HC family and typically provide standard CMOS output drive. The 74HC541D is specified for bus-driving applications with 3-state outputs, while the 74HC594D provides standard push-pull parallel outputs. Actual drive current should be verified from the specific manufacturer datasheet.
Do the 74HC541D and 74HC594D operate at the same supply voltage range?
Yes. As 74HC-series devices, both typically operate over a supply voltage range of 2 V to 6 V. Exact limits and recommended operating conditions should be confirmed from the manufacturer datasheet for the specific part number.
Which device is better suited for expanding microcontroller I/O?
The 74HC594D is better suited for I/O expansion because it converts serial data from a microcontroller into eight parallel outputs using few control lines. The 74HC541D is better suited for buffering, driving, or isolating existing parallel signals rather than expanding I/O count.
Are the 74HC541D and 74HC594D available in the same package type?
Both are commonly offered in SOIC-16 and other standard 16-pin packages, but package availability depends on the manufacturer and specific ordering code. Designers must verify the exact package, pinout, and thermal characteristics from the manufacturer datasheet before layout or substitution.