Texas Instruments SN74LVC3G98PWR

Overview

SN74LVC3G98 from Texas Instruments is a triple-channel configurable logic gate IC with Schmitt-trigger inputs, supporting MUX, AND, OR, NAND, NOR, inverter, and non-inverter functions across three independent 3-input logic blocks. It operates from 1.1V to 3.6V supply, features 5.5V-tolerant inputs, and delivers propagation delays as low as 5.6 ns at 3.3V - used in power sequencing, signal enable control, and noise-immune digital interfacing in industrial MCU systems.

For engineers reviewing the SN74LVC3G98 datasheet, SN74LVC3G98 pinout, SN74LVC3G98 application, or SN74LVC3G98 equivalent, this page provides verified functional modes, real-world timing behavior under 15–50 pF loads, Schmitt-trigger hysteresis values (0.07–1.2 V), absolute maximum ratings (6.5 V input tolerance), and validated TSSOP-14 and WQFN-14 package mappings - all confirmed against TI's SCLSA08A (May 2024) production datasheet.

Technical Context

The SN74LVC3G98 implements three independent 3-input configurable logic cells, each selecting output state via an 8-row truth table mapping A/B/C inputs to Y output. Each channel uses CMOS Schmitt-trigger inputs with voltage-dependent hysteresis (ΔVT = 0.07–1.2 V), enabling robust operation with slow-rising or noisy signals without external filtering.

Outputs are balanced CMOS push-pull drivers capable of ±24 mA sink/source at 3.0 V, with VOH ≥ 2.2 V and VOL ≤ 0.55 V under full load. The device supports mixed-voltage interfacing via 5.5V-tolerant inputs while powered from as low as 1.1V, and includes ESD protection exceeding 2000V HBM and 1000V CDM per JESD22.

Key Specifications

Pinout & Package

SN74LVC3G98 is available in two RoHS-compliant packages: PW (14-pin TSSOP, 5.0 mm × 6.4 mm body) and BQA (14-pin WQFN, 3.0 mm × 2.5 mm body with exposed thermal pad). Both packages support standard PCB assembly and thermal relief via GND-connected thermal pad (BQA only).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar configurable logic gate applications.

Compared with SN74LVC3G98, SN74LVC1G98DBVR offers footprint reduction at the cost of channel count, while NC7SZ98P6X lacks critical 5.5V input tolerance - making SN74LVC3G98 the only option supporting robust mixed-voltage interfacing and triple-function consolidation in a single 14-pin package.

Availability

SN74LVC3G98 is available at Aetrix Electronics and suitable for industrial control systems, automotive body electronics, and portable medical devices requiring stable component supply, long-term lifecycle support, and dual-package flexibility (TSSOP and WQFN).

Supply support for SN74LVC3G98 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions, with over 50 years of innovation in high-reliability industrial and automotive components.

The SN74LVC3G98 belongs to TI's LVC low-voltage logic family, designed specifically for space-constrained, noise-prone applications requiring flexible logic configuration, wide supply range, and robust ESD performance - targeting power management, sensor interface, and MCU peripheral control.

FAQ

What logic functions does the SN74LVC3G98 support per channel?

The SN74LVC3G98 supports eight logic configurations per channel - MUX, AND, OR, NAND, NOR, inverter, and non-inverter - selected by the combination of its three inputs (A, B, C). This is defined in Table 7-1 of the datasheet and implemented via internal combinational logic, not programmable memory. Each of the three independent channels on the SN74LVC3G98 can be configured separately to any of these functions simultaneously.

Does the SN74LVC3G98 require external pull-up or pull-down resistors on unused inputs?

Unused inputs on the SN74LVC3G98 must be terminated to either VCC or GND - they cannot be left floating. A 10-kΩ resistor is recommended for pull-up/pull-down biasing to ensure stable logic states and prevent increased dynamic current consumption. This requirement applies to all six input pins per active channel (A/B/C), and termination is mandatory even when a channel is not used, as floating inputs degrade noise immunity and increase ICC.

Can the SN74LVC3G98 drive a 50-pF capacitive load while meeting timing specifications?

Yes - the SN74LVC3G98 is fully characterized for 50-pF loads, with tpd = 5.6 ns at 3.3V ± 0.3V and CL = 50pF (Section 5.6). Driving larger capacitances is possible but degrades propagation delay and increases dynamic current; TI recommends limiting total load to ≤50pF unless a series resistor is added to limit output current per Absolute Maximum Ratings. The SN74LVC3G98's push-pull output structure supports this directly without external components.

What is the purpose of the thermal pad on the SN74LVC3G98 BQA package?

The exposed thermal pad on the SN74LVC3G98 BQA (WQFN) package must be soldered to a GND plane to achieve optimal thermal performance - RθJB drops to 70.9°C/W when connected, versus undefined behavior if left floating. It is electrically tied to GND internally and must never connect to VCC or signal nets. This pad significantly improves power dissipation during sustained output switching, especially at 125°C ambient, and is required for compliance with JEDEC thermal test conditions.

How does the Schmitt-trigger input architecture improve noise immunity in the SN74LVC3G98?

The SN74LVC3G98's Schmitt-trigger inputs provide voltage hysteresis (ΔVT = 0.07–1.2 V depending on VCC), meaning the threshold for detecting a rising edge (VT+) differs from that for a falling edge (VT−). This prevents multiple toggles when input signals cross a single threshold amid noise. For example, at 3.0V supply, ΔVT ≥ 0.3 V allows rejection of up to 300 mVpp noise - critical for reliable operation with slow-switching sensors or mechanical switches without external filtering.