Texas Instruments SN74AHC74RGYRG4

Overview

SN74AHC74RGYRG4 from Texas Instruments is a dual positive-edge-triggered D-type flip-flop with independent asynchronous clear (CLR) and preset (PRE) inputs, operating from 2 V to 5.5 V supply. It delivers 110 MHz maximum clock frequency at 5 V, 14 ns propagation delay (tPLH/tPHL), and ±8 mA output drive. Used in digital logic control, clock division, and signal debouncing circuits within industrial controllers and embedded interfaces.

For engineers reviewing the SN74AHC74RGYRG4 datasheet, SN74AHC74RGYRG4 pinout, SN74AHC74RGYRG4 application, or SN74AHC74RGYRG4 equivalent, key selection criteria include its VQFN-14 package thermal performance (RθJA = 87.1 °C/W), dual-channel edge-triggered storage behavior, guaranteed setup/hold timing (tsu = 5 ns, th = 0.5 ns at 5 V), and robust ESD protection (±2000 V HBM).

Technical Context

The SN74AHC74RGYRG4 implements two independent D-type latches synchronized to the rising edge of CLK, with active-low asynchronous PRE and CLR controlling Q and Q outputs regardless of clock state. Each channel operates with identical timing and electrical characteristics across the full 2–5.5 V supply range.

Its CMOS AHC logic family ensures rail-to-rail output swing, low static current (ICC ≤ 20 µA), and input transition rate tolerance up to 100 ns/V at 3.3 V. The device supports mixed-voltage interfacing and meets JESD 17 latch-up (>250 mA) and JESD 22 ESD standards.

Key Specifications

Pinout & Package

VQFN-14 package (RGY) with exposed thermal pad; 3.5 mm × 3.5 mm body, 0.5 mm pitch, 14 terminals including GND, VCC, and two fully independent flip-flop channels.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual D-type flip-flop applications.

Compared with SN74LVC74APWRE4 and MC74VHC74DT, the SN74AHC74RGYRG4 offers superior 2 V minimum supply support, tighter timing (8.5 ns vs 12 ns), and certified ±2000 V HBM robustness - making it optimal for industrial reset hold and noise-immune toggle applications where supply headroom and reliability are critical.

Availability

SN74AHC74RGYRG4 is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and embedded control systems requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for SN74AHC74RGYRG4 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 ICs with over 90 years of innovation in industrial, automotive, and communications markets.

The SN74AHC74RGYRG4 belongs to TI's advanced high-speed CMOS (AHC) logic family, designed specifically for low-power, high-noise-immunity digital control in space-constrained and thermally demanding applications.

FAQ

What is the maximum clock frequency supported by the SN74AHC74RGYRG4?

The SN74AHC74RGYRG4 supports a maximum clock frequency of 110 MHz when operated at VCC = 5 V ± 0.5 V with CL = 15 pF load. At 3.3 V ± 0.3 V, the maximum frequency drops to 70 MHz. These values are specified in the Switching Characteristics section of the official datasheet and reflect guaranteed performance across the full –40 °C to +125 °C temperature range.

Does the SN74AHC74RGYRG4 require external pull-up or pull-down resistors on unused inputs?

Yes, all unused inputs of the SN74AHC74RGYRG4 must be terminated to either VCC or GND to prevent floating states that cause increased power consumption and potential logic instability. TI recommends 10-kΩ resistors for default HIGH (pull-up) or LOW (pull-down) biasing. Leaving inputs unconnected violates the Recommended Operating Conditions and may result in undefined output behavior.

Can the SN74AHC74RGYRG4 operate reliably at 2.0 V supply voltage?

Yes, the SN74AHC74RGYRG4 is fully specified to operate down to 2.0 V supply voltage across its entire commercial temperature range (–40 °C to +125 °C). At 2 V, it maintains functional timing (tsu = 7 ns, tPLH = 14.5 ns), output drive (±50 µA), and logic thresholds (VIH = 1.5 V, VIL = 0.5 V), enabling use in battery-powered or low-voltage legacy systems where 3.3 V rails are unavailable.

What is the purpose of the exposed thermal pad on the SN74AHC74RGYRG4 VQFN package?

The exposed thermal pad on the SN74AHC74RGYRG4 serves as the primary heat dissipation path from the silicon die to the PCB. It must be soldered directly to a solid copper ground plane to achieve the specified junction-to-ambient thermal resistance of 87.1 °C/W. Omitting thermal pad connection increases junction temperature significantly and risks exceeding the 150 °C absolute maximum rating under sustained 8 mA output loading.

How does the SN74AHC74RGYRG4 handle simultaneous assertion of PRE and CLR inputs?

When both PRE and CLR are asserted low simultaneously on the same channel of the SN74AHC74RGYRG4, the output enters a metastable state (Q = Q = HIGH), which is explicitly marked as unstable in the function table. Upon release of either PRE or CLR, the output resolves to a valid logic state determined by the last active control signal - this behavior is not latched and must be avoided in deterministic designs by ensuring mutually exclusive PRE/CLR activation.