Part A
74LCX04MTCX
Semi - conducteurs
- Lifecycle
- Active
- Stock
- 4842 PCS
- Package
- TSSOP-14
- Series
- Logique - portes et Onduleurs
Replacement verdict
Not a drop-in replacement
The 74LCX04MTCX and 74LCX16501MTDX are not functionally interchangeable. The 74LCX04MTCX is a hex inverter providing six independent NOT gates, while the 74LCX16501MTDX is an 18-bit universal bus transceiver with registered and unregistered data paths. Their logic functions, pin counts, and package footprints differ fundamentally, so neither device can directly substitute for the other in an existing design.
Different logic function
Different channel count
Different pin count
Different package footprint
Parts at a glance
Part B
74LCX16501MTDX
Fairchild Semiconductor Inc
- Lifecycle
- Active
- Stock
- 6048 PCS
- Package
- TFSOP-56
- Series
- Logique - fonction bus universel
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | 74LCX04MTCX | 74LCX16501MTDX | Why it matters |
|---|---|---|---|
| Logic Function | Hex Inverter | 18-Bit Universal Bus Transceiver | The logic function defines the core operation of the device; different functions are not functionally substitutable. |
| Number of Circuits / Channels | 6 | 18 | Channel count determines how many signal lines the device can process, affecting board layout and application suitability. |
| Package / Case | 14-TSSOP | 56-TSSOP | Package type and pin count must match the PCB footprint for a drop-in replacement. |
| Number of Pins | 14 | 56 | Pin count must match the board layout; a mismatch prevents direct substitution. |
| Supply Voltage Range | 2.0 V to 3.6 V | 2.0 V to 3.6 V | Operating voltage range must be compatible with the system power rails for correct logic levels and safe operation. |
| Logic Family | LCX | LCX | Same logic family ensures compatible input/output thresholds and switching characteristics. |
| Output Type | Single-Ended | 3-State, Single-Ended | Output type affects bus sharing capability; 3-state outputs allow connection to shared buses while standard outputs do not. |
| Mounting Type | Surface Mount | Surface Mount | Mounting type must match the assembly process; both are surface mount but package differences still apply. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | Temperature range must cover the application environment for reliable operation. |
| Propagation Delay (Max) | 5.2 ns at 3.3 V | 6.5 ns at 3.3 V | Propagation delay affects timing margins in synchronous systems; different delays may require timing re-analysis. |
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Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 74LCX04MTCX | 74LCX16501MTDX |
|---|---|---|
| Supplier | - | Rochester Electronics, LLC |
| Series | 74LCX | 74LCX |
| Part Status | Active | Active |
| Logic Type | Inverter | Universal Bus Transceiver |
| Number of Circuits | 6 | 18-Bit |
| Current - Output High Low | 24mA, 24mA | 24mA, 24mA |
| Voltage - Supply | 2V ~ 3.6V | 2V ~ 3.6V |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Mounting Type | Surface Mount | Surface Mount |
| Number of Inputs | 1 | - |
| Current - Quiescent (Max) | 10 µA | - |
| Logic Level - Low | 0.7V ~ 0.8V | - |
| Logic Level - High | 1.7V ~ 2V | - |
| Max Propagation Delay @ V Max CL | 5.2ns @ 3.3V, 50pF | - |
Frequently asked questions
What are the primary functional differences between the 74LCX04MTCX and the 74LCX16501MTDX?
The 74LCX04MTCX is a hex inverter, providing six independent NOT gates with standard push-pull outputs. The 74LCX16501MTDX is a 16-bit universal bus transceiver with 3-state outputs, designed for bidirectional asynchronous communication between data buses. They serve fundamentally different logic functions and are not pin-to-pin or function-to-function replacements.
Are the 74LCX04MTCX and 74LCX16501MTDX pin-compatible?
No. The 74LCX04MTCX is offered in a 14-pin TSSOP package, while the 74LCX16501MTDX is offered in a 56-pin TSSOP package. The pin counts, pin assignments, and package footprints are different, so they cannot be interchanged on the same PCB land pattern.
Do both devices operate at the same supply voltage and logic levels?
Yes. Both the 74LCX04MTCX and 74LCX16501MTDX are LCX-family devices specified for a 2.0 V to 3.6 V VCC operating range, with 5 V tolerant inputs and outputs. They support low-voltage 3.3 V logic systems while allowing interfacing to 5 V logic without external level shifting.
What is the difference in output drive current between the two parts?
The 74LCX04MTCX provides ±24 mA output drive at 3.0 V VCC, suitable for standard logic fan-out and moderate load driving. The 74LCX16501MTDX provides ±24 mA output drive as well, but across 16 bidirectional channels with 3-state control, making it intended for bus-oriented applications rather than simple inversion.
Can the 74LCX16501MTDX be used to replace the 74LCX04MTCX in an inverter application?
No. The 74LCX16501MTDX is a bus transceiver with non-inverting true and complementary outputs controlled by direction and output-enable pins. It does not provide the logic inversion function of the 74LCX04MTCX, and its 56-pin package and control architecture are not compatible with a 14-pin hex inverter socket.
What are the typical propagation delays for these devices?
The 74LCX04MTCX has a typical propagation delay of approximately 4.5 ns at 3.3 V VCC. The 74LCX16501MTDX has a typical propagation delay of approximately 5.0 ns at 3.3 V VCC. Both values are consistent with LCX-family high-speed CMOS performance, though actual delays depend on load, temperature, and supply voltage.
Which device is better suited for bidirectional bus interfacing?
The 74LCX16501MTDX is specifically designed for bidirectional bus interfacing, featuring 16-bit universal bus transceiver functionality with 3-state outputs, direction control, and output-enable inputs. The 74LCX04MTCX is a unidirectional hex inverter and is not intended for bus transceiver applications.
Are both devices available in the same package type?
Both devices are available in TSSOP packages, but with different pin counts. The 74LCX04MTCX uses a 14-pin TSSOP, while the 74LCX16501MTDX uses a 56-pin TSSOP. The package family is similar, but the physical dimensions and pin counts differ, preventing direct substitution.