MC74VHC1GT126DFT1G

Overview

The MC74VHC1GT126DFT1G is a single-channel non-inverting 3-state buffer from the VHC logic family, manufactured by onsemi. It operates within a supply voltage range of 2.0 V to 5.5 V and features TTL-level input thresholds. The device provides high noise immunity through a buffered three-stage internal circuit and includes over-voltage tolerant inputs and outputs up to 5.5 V, enabling safe interfacing between 5 V and 3 V circuits. It supports partial power-down protection via IOFF and delivers source/sink currents of 8 mA at 3.0 V. Packaged in SC-88A (SOT-353), it ensures stable output performance across an operating temperature range of -55°C to +125°C.

Feature Summary

• TTL-level input thresholds for direct compatibility with TTL-driven systems
• Over-voltage tolerant I/O structures protect against voltage mismatches during hot insertion or battery backup scenarios
• IOFF feature enables partial power-down protection to minimize leakage current when the device is powered off
• Three-stage buffered design provides high noise immunity and stable signal transmission

Applications

• Interfacing 5 V logic circuits with 3 V logic circuits
• Clock buffering and distribution in digital systems
• Signal isolation and line driving in portable electronic devices
• Memory address/data bus drivers requiring tri-state control

Procurement Notes

Verify the specific suffix 'DF' corresponds to the SC-88A package and standard commercial grade before ordering. Confirm that the TTL-threshold variant (GT) matches the system's input requirements rather than the CMOS-threshold version. Ensure the tape-and-reel quantity aligns with production needs. Check for any automotive '-Q' suffix requirements if the application demands AEC-Q100 qualification. Validate RoHS compliance status for environmental regulations.

Selection Notes

Select this component when TTL-compatible input thresholds are required for a single-channel buffer. The SC-88A package offers a compact footprint suitable for space-constrained designs. Consider the 3-state output capability if bus sharing or tri-state control is necessary. Evaluate the 8 mA drive strength against load requirements. Compare propagation delay specifications against system timing constraints at the intended operating voltage.

Part Context

This part belongs to the MC74VHC1G126/MC74VHC1GT126 series of single-gate non-inverting 3-state buffers. The 'GT' designation specifically indicates TTL-level input thresholds, distinguishing it from the 'G126' variant which uses CMOS-level thresholds. Both share identical electrical characteristics regarding output drive, power consumption, and packaging options, differing only in input threshold voltage definitions.

Replacement Considerations

MC74VHC1G126DFT1G serves as a CMOS-threshold alternative within the same package and pinout configuration.