Part A
74VHC14MTCX
온세미
- Lifecycle
- Active
- Stock
- 4330 PCS
- Package
- TSSOP-14
- Series
- 로직 - 도어 및 인버터
Replacement verdict
Not a drop-in replacement
The 74VHC14MTCX and 74VHCT74ATTR are functionally incompatible devices that cannot serve as substitutes for one another. The 74VHC14MTCX is a hex Schmitt-trigger inverter featuring six independent inverting channels with hysteresis, while the 74VHCT74ATTR is a dual D-type flip-flop with edge-triggered storage elements. Their fundamental logic functions, channel configurations, pin assignments, and package footprints differ entirely, making direct replacement impossible without complete circuit redesign.
Different logic function
Different channel count
Different pin configuration
Different package footprint
Parts at a glance
Part B
74VHCT74ATTR
ST마이크로일렉트로닉스(주)
- Lifecycle
- Active
- Stock
- 2414 PCS
- Series
- 논리 - 트리거
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | 74VHC14MTCX | 74VHCT74ATTR | Why it matters |
|---|---|---|---|
| Logic Function | Hex Schmitt Trigger Inverter | Dual D-Type Flip-Flop with Preset and Clear | The logic function defines the fundamental operation of the device; different functions are not functionally substitutable. |
| Logic Family | VHC (Very High Speed CMOS) | VHCT (Very High Speed CMOS with TTL-compatible inputs) | The logic family determines input threshold compatibility and interfacing with other logic levels. |
| Number of Circuits | 6 | 2 | The number of circuits per package affects how many independent signal paths can be handled. |
| Input Type | Schmitt Trigger | TTL-Compatible | Schmitt trigger inputs provide hysteresis for noise immunity, while TTL-compatible inputs allow direct interfacing with TTL logic levels. |
| Output Type | Inverting | Non-Inverting (Q) and Inverting (Q-bar) | Output polarity determines the logic state relationship between input and output signals. |
| Supply Voltage Range | 2.0 V to 5.5 V | 4.5 V to 5.5 V | The supply voltage range determines compatibility with the system power rail and allowable operating conditions. |
| Propagation Delay | ~10.6 ns at 5 V | ~8.5 ns at 5 V | Propagation delay affects maximum operating frequency and timing margins in synchronous designs. |
| Package Type | TSSOP-14 | TSSOP-14 | Package type affects PCB footprint, thermal characteristics, and assembly compatibility. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | The operating temperature range defines the environmental conditions under which the device functions reliably. |
| Output Drive Current | ±8 mA | ±8 mA | Output drive current determines the ability to drive loads such as LEDs, other logic inputs, or transmission lines. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 74VHC14MTCX | 74VHCT74ATTR |
|---|---|---|
| Supplier | - | STMicroelectronics |
| Series | - | 74VHCT |
| Part Status | Active | Obsolete |
| Function | - | Set(Preset) and Reset |
| Type | - | D-Type |
| Output Type | - | Complementary |
| Number of Elements | - | 2 |
| Number of Bits per Element | - | 1 |
| Clock Frequency | - | 140 MHz |
| Max Propagation Delay @ V Max CL | - | 8.8ns @ 5V, 50pF |
| Trigger Type | - | Positive Edge |
| Current - Output High Low | - | 8mA, 8mA |
| Voltage - Supply | - | 4.5V ~ 5.5V |
| Current - Quiescent (Iq) | - | 2 µA |
| Input Capacitance | - | 6 pF |
| Operating Temperature | - | -55°C ~ 125°C (TA) |
| Mounting Type | - | Surface Mount |
Frequently asked questions
What are the basic functions of the 74VHC14MTCX and 74VHCT74ATTR?
The 74VHC14MTCX is a hex Schmitt-trigger inverter from the VHC family, while the 74VHCT74ATTR is a dual D-type flip-flop with preset and clear from the VHCT family. They perform different logic functions and are not functionally equivalent.
What are the key differences between the 74VHC14MTCX and 74VHCT74ATTR?
The 74VHC14MTCX provides six inverting Schmitt-trigger channels in a TSSOP-14 package, whereas the 74VHCT74ATTR contains two edge-triggered D flip-flops with asynchronous preset and clear in a TSSOP-14 package. The VHC device is designed for 2.0 V to 5.5 V operation, while the VHCT device is optimized for 4.5 V to 5.5 V operation with TTL-compatible inputs.
Are the 74VHC14MTCX and 74VHCT74ATTR pin-to-pin compatible?
No. Although both devices are offered in a TSSOP-14 package, their pin functions and internal logic differ. The 74VHC14MTCX uses the pins for six independent inverter channels, while the 74VHCT74ATTR uses the pins for two flip-flops with preset, clear, clock, and data inputs. They cannot be interchanged without redesigning the circuit.
What are the recommended operating voltage ranges for these devices?
The 74VHC14MTCX operates over a recommended supply voltage range of 2.0 V to 5.5 V. The 74VHCT74ATTR operates over a recommended supply voltage range of 4.5 V to 5.5 V. These ranges are specified in the respective manufacturer datasheets.
What logic families do the 74VHC14MTCX and 74VHCT74ATTR belong to?
The 74VHC14MTCX belongs to the VHC (Very High Speed CMOS) family, which features balanced output drive and CMOS-compatible inputs. The 74VHCT74ATTR belongs to the VHCT (Very High Speed CMOS with TTL-compatible inputs) family, which is designed to interface directly with TTL logic levels while maintaining CMOS output characteristics.
What are the typical propagation delays for these devices?
The 74VHC14MTCX typically exhibits a propagation delay of approximately 5.5 ns at 5.0 V supply. The 74VHCT74ATTR typically exhibits a propagation delay of approximately 6.5 ns at 5.0 V supply. These values are typical and can vary with load, temperature, and supply voltage; refer to the manufacturer datasheet for guaranteed limits.
Can the 74VHC14MTCX and 74VHCT74ATTR be used in the same design?
Yes, they can be used in the same design if the supply voltage and logic level requirements are compatible. The 74VHC14MTCX can operate at 5.0 V and its CMOS outputs can drive the 74VHCT74ATTR inputs, which are TTL-compatible. However, the designer must verify timing, fan-out, and signal integrity for the specific application.
What are the package options for the 74VHC14MTCX and 74VHCT74ATTR?
The 74VHC14MTCX is available in a TSSOP-14 package, indicated by the "MTC" suffix. The 74VHCT74ATTR is available in a TSSOP-14 package, indicated by the "TTR" suffix. Both are surface-mount packages, but their pinouts and functions differ as noted above.