Part A
74VHC541FT
Toshiba Semiconductor và lưu trữ
- Lifecycle
- Active
- Stock
- 5516 PCS
- Package
- TSSOP-20
- Series
- Logic - Buffers, Drivers, Receivers, Transceivers
Replacement verdict
Compatible functional replacement candidate
The 74VHC541FT and 74VHC240M are both octal buffers from the VHC family, but they are not pin-compatible drop-in replacements. The 74VHC541FT provides non-inverting 3-state outputs in a TSSOP-20 package, while the 74VHC240M provides inverting 3-state outputs in an SOIC-20 package. Designers must account for the inverted logic polarity and the different land pattern before substituting one for the other.
Output Type
Validation required
Channel Count
High match
Package Type
Not compatible
Supply Voltage Range
High match
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | 74VHC541FT | 74VHC240M | Why it matters |
|---|---|---|---|
| Logic Function | Octal Buffer/Line Driver, non-inverting, 3-state | Octal Buffer/Line Driver, inverting, 3-state | Determines output polarity; non-inverting vs inverting changes signal phase and prevents direct functional substitution. |
| Output Enable Polarity | Active-low OE1 and OE2 (both must be low to enable) | Active-low OE1 and OE2 (both must be low to enable) | Affects how the device is controlled in a circuit; matching polarity ensures compatible control logic. |
| Number of Channels | 8 | 8 | Channel count must match to preserve bus width and signal routing in the target design. |
| Supply Voltage Range | 2.0 V to 5.5 V | 2.0 V to 5.5 V | Defines compatible power rails; overlapping ranges allow use in 3.3 V and 5 V systems. |
| Output Drive Current | ±8 mA at 5 V | ±8 mA at 5 V | Determines fan-out and ability to drive loads; identical drive supports similar load conditions. |
| Propagation Delay | ~5.5 ns at 5 V | ~5.5 ns at 5 V | Affects timing margins in synchronous systems; similar delays ease timing compatibility. |
| Package Type | TSSOP-20 | SOIC-20 | Footprint and thermal characteristics differ; PCB layout and assembly must accommodate the package. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Ensures reliable operation across environmental conditions; matching ranges supports similar applications. |
| Input Type | CMOS | CMOS | Input structure affects threshold levels and compatibility with driving logic families. |
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 | 74VHC541FT | 74VHC240M |
|---|---|---|
| Supplier | - | onsemi |
| Series | 74VHC | 74VHC |
| Part Status | Active | Obsolete |
| Logic Type | Buffer, Non-Inverting | Buffer, Inverting |
| Number of Elements | 1 | 2 |
| Number of Bits per Element | 8 | 4 |
| Output Type | 3-State | 3-State |
| Current - Output High Low | 8mA, 8mA | 8mA, 8mA |
| Voltage - Supply | 2V ~ 5.5V | 2V ~ 5.5V |
| Operating Temperature | -40°C ~ 125°C (TA) | -40°C ~ 85°C (TA) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the primary functional differences between the 74VHC541FT and the 74VHC240M?
The 74VHC541FT is an octal non-inverting buffer/line driver with 3-state outputs, while the 74VHC240M is an octal inverting buffer/line driver with 3-state outputs. The key difference is logic polarity: the 541FT passes signals without inversion, whereas the 240M inverts each signal.
Are the 74VHC541FT and 74VHC240M pin-compatible?
No. The 74VHC541FT typically uses a TSSOP-20 package with a specific pinout for non-inverting buffers, while the 74VHC240M uses an SOIC-20 package with a different pinout for inverting buffers. Pin functions and enable pin locations differ, so they are not drop-in replacements.
Can the 74VHC541FT and 74VHC240M operate at the same supply voltage range?
Yes. Both devices are members of the 74VHC family and operate over a recommended supply voltage range of 2.0 V to 5.5 V, with typical operation at 3.3 V or 5 V.
Do both the 74VHC541FT and 74VHC240M have 3-state outputs?
Yes. Both devices feature 3-state outputs that can be placed in a high-impedance state via output enable (OE) pins, allowing them to be used in bus-oriented applications.
What is the difference in output drive current between the 74VHC541FT and 74VHC240M?
Both devices typically provide ±8 mA output drive at 5 V VCC, which is standard for the 74VHC logic family. No significant drive current difference exists between these two parts under identical supply and temperature conditions.
Which device is better for signal buffering where signal polarity must be preserved?
The 74VHC541FT is the correct choice when signal polarity must be preserved, because it is a non-inverting buffer. The 74VHC240M inverts the signal and would change the logic state.
Are the 74VHC541FT and 74VHC240M interchangeable in an existing PCB design?
No. They differ in logic function (non-inverting vs inverting), package type (TSSOP-20 vs SOIC-20), and pinout. Substitution requires a new PCB layout and verification that the logic inversion is acceptable or compensated elsewhere in the circuit.
Do both devices support the same operating temperature range?
Yes. Both the 74VHC541FT and 74VHC240M are specified for the industrial temperature range of −40 °C to +85 °C, making them suitable for similar environmental conditions.