STMicroelectronics 74LVC32ATTR

Overview

74LVC32ATTR from STMicroelectronics is a low-voltage CMOS quad 2-input OR gate operating from 1.65 V to 3.6 V, with 5 V tolerant inputs, 4.2 ns max propagation delay at 3 V, ±24 mA output drive, and pin/function compatibility with standard 74-series 32 logic. It enables robust level-shifting in mixed-voltage 3.3 V/5 V systems such as industrial I/O controllers and FPGA interface buffers.

For engineers reviewing the 74LVC32ATTR datasheet, 74LVC32ATTR pinout, 74LVC32ATTR application, or 74LVC32ATTR equivalent, key selection criteria include its 5 V tolerant input capability, symmetrical 24 mA drive strength at 3 V, -55 °C to +125 °C operating range, PCI bus compliance at 24 mA, and latch-up immunity exceeding 500 mA per JESD17.

Technical Context

This device implements four independent OR logic functions using sub-micron C2MOS technology, supporting true bidirectional voltage translation between 3.3 V logic domains and legacy 5 V signal sources. Its input protection circuitry ensures 2 kV HBM ESD immunity and power-down safe operation with high-impedance inputs/outputs when VCC = 0 V.

The symmetric output impedance (|IOH| = IOL ≥ 24 mA at VCC = 3 V) and balanced tPLH ≅ tPHL propagation delays enable clean signal integrity in timing-critical combinatorial paths. Absolute maximum ratings permit transient input voltages up to 7 V, while recommended operating conditions guarantee truth table functionality from 1.2 V to 3.6 V.

Key Specifications

Pinout & Package

TSSOP-14 package (JEDEC MO-153, 4.4 mm × 5.0 mm body, 0.65 mm pitch), thermally enhanced for high-density PCB layouts and reflow-compatible assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad 2-input OR gate applications.

Compared with SN74LVC32APWR and 74AHC32PW,118, the 74LVC32ATTR uniquely combines 5 V input tolerance with industrial temperature range and PCI-compliant drive strength - making it optimal for mixed-voltage industrial control where reliability trumps raw speed.

Availability

74LVC32ATTR is available at Aetrix Electronics and suitable for industrial PLC I/O modules, FPGA configuration interfaces, automotive body control units, and PCIe slot power sequencing requiring stable component supply across extended temperature and mixed-voltage environments.

Supply support for 74LVC32ATTR 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, Switzerland, designing and manufacturing analog, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The 74LVC32A belongs to ST's LVC (Low-Voltage CMOS) logic family, engineered specifically for interoperability between 3.3 V and 5 V systems while delivering high speed, low power, and robust ESD/latch-up performance.

FAQ

Can 74LVC32ATTR operate reliably at 1.65 V supply?

Yes - the device is fully specified down to 1.65 V, with guaranteed truth table operation, 4 mA output drive, and VIH/VIL thresholds scaled to 0.65×VCC and 0.35×VCC respectively. At this minimum voltage, propagation delay increases to 8.9 ns (max), and output swing remains rail-to-rail.

Is external pull-up or pull-down required on unused inputs?

No - unused inputs may be tied directly to VCC or GND without external resistors. The input leakage current is ≤ ±5 µA at 3.6 V, and internal protection diodes prevent floating states. Leaving inputs unconnected risks noise-induced switching and increased ICC.

Does 74LVC32ATTR support hot insertion when VCC is off?

Yes - its power-down protection ensures inputs and outputs enter high-impedance state with ≤10 µA off-state leakage when VCC = 0 V. This prevents back-driving of powered subsystems and satisfies IEC 61000-4-2 Level 4 ESD survivability during live insertion.

What is the maximum capacitive load this device can drive at 3.3 V?

At VCC = 3.3 V, the device maintains 4.2 ns max tPD driving 50 pF loads per output. For heavier loads (>70 pF), propagation delay increases linearly; measured CPD is 37 pF, indicating typical dynamic current draw of ~1.2 mA per MHz of input toggle rate under 50 pF load.