STMicroelectronics 74VHCT05ATTR

Overview

74VHCT05ATTR from STMicroelectronics is a high-speed CMOS open-drain hex inverter with TTL-compatible inputs, 3.5 ns typical propagation delay at 5 V, 2 µA max quiescent current, and operation across 4.5–5.5 V supply. It serves as a level-shifting logic buffer in bus interface circuits requiring active-low open-drain outputs for wired-AND or I²C pull-up applications.

For engineers reviewing the 74VHCT05ATTR datasheet, 74VHCT05ATTR pinout, 74VHCT05ATTR application, or 74VHCT05ATTR equivalent, key selection criteria include open-drain output drive capability (8 mA sink), input voltage tolerance up to 7 V independent of VCC, latch-up immunity, ESD protection (2 kV HBM), and compatibility with legacy 74-series logic footprints.

Technical Context

This device implements six independent inverting buffers with open-drain outputs, enabling wired-logic configurations and bidirectional bus interfacing. Its input structure accepts 0–7 V regardless of VCC, supporting mixed-voltage domain translation (e.g., 5 V logic driving 3.3 V or lower systems).

The internal three-stage C2MOS design provides high noise immunity and stable switching, while power-down protection prevents back-driving damage when VCC = 0 V. All inputs and outputs feature integrated ESD protection diodes rated to ±20 mA DC clamp current.

Key Specifications

Pinout & Package

TSSOP-14 package: 4.9–5.1 mm width, 6.2–6.6 mm length, 1.2 mm height, 0.65 mm pitch, lead-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar open-drain hex inverter applications.

Compared with SN74LVC05APW and 74AHC05PW, the 74VHCT05ATTR uniquely combines 5 V operation, true open-drain outputs, 7 V input tolerance, and TTL compatibility-making it the sole choice for legacy 5 V bus interfacing with robustness requirements.

Availability

74VHCT05ATTR is available at Aetrix Electronics and suitable for I²C bus design, industrial backplane interfacing, legacy system upgrades, and hot-swap peripheral integration requiring stable component supply and long-term obsolescence management.

Supply support for 74VHCT05ATTR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The VHCT logic family targets high-speed, low-power 5 V CMOS applications requiring TTL compatibility and enhanced robustness-specifically for industrial control, instrumentation, and legacy system modernization.

FAQ

Can 74VHCT05ATTR be used with a 3.3 V supply?

No. The 74VHCT05ATTR is specified only for 4.5–5.5 V operation. Its TTL-compatible input thresholds (V_IH ≥ 2.0 V, V_IL ≤ 0.8 V) and internal C2MOS structure require nominal 5 V biasing. Using 3.3 V may cause marginal or non-functional switching and violates recommended operating conditions.

Does this device support true bidirectional I²C communication?

No. The 74VHCT05ATTR is a unidirectional inverter with open-drain outputs. It can condition or translate I²C signals (e.g., SDA/SCL) but cannot replace a dedicated bidirectional I²C buffer like the PCA9515A. External pull-ups and proper master/slave protocol handling remain required.

What is the maximum sink current per output under continuous operation?

The absolute maximum DC output current is ±25 mA, but the recommended operating limit is 8 mA per output at V_OL ≤ 0.44 V (V_CC = 4.5 V). Exceeding 8 mA risks exceeding VOL specs and thermal limits in TSSOP-14 packaging, especially across temperature extremes.

Is the 74VHCT05ATTR pin-compatible with standard 74HC05?

Yes-pinout and logic function match the 74-series 05 family-but electrical behavior differs. Unlike 74HC05 (push-pull), the 74VHCT05ATTR has open-drain outputs and TTL-compatible inputs. Direct substitution requires verifying that the target application relies on open-drain functionality and tolerates the different output structure.