Texas Instruments SN74LS73ADRG4

Overview

SN74LS73ADRG4 from Texas Instruments is a dual J-K flip-flop with individual asynchronous clear inputs, fabricated in LS-TTL logic, operating at 0°C to 70°C, with typical propagation delay of 15 ns and maximum supply current of 24 mA, used in synchronous digital control circuits such as counters and state machines.

For engineers reviewing the SN74LS73ADRG4 datasheet, SN74LS73ADRG4 pinout, SN74LS73ADRG4 application, or SN74LS73ADRG4 equivalent, this device serves as a legacy-compatible edge-triggered memory element requiring precise clock timing, low-power TTL-level interfacing, and deterministic reset behavior in industrial control and instrumentation designs.

Technical Context

The SN74LS73ADRG4 implements two independent negative-edge-triggered J-K flip-flops, each with active-low asynchronous clear (CLR̅), no preset input, and complementary Q and Q̅ outputs. It uses bipolar transistor–transistor logic (TTL) with Schottky clamping for speed and noise immunity.

Its operation requires a clean, monotonic falling clock edge for state transition; setup and hold times are specified at 20 ns and 5 ns respectively relative to CLK, and it drives standard TTL loads (fan-out of 10) while maintaining compatible voltage thresholds (VIH = 2.0 V min, VIL = 0.8 V max).

Key Specifications

Pinout & Package

SN74LS73ADRG4 is packaged in a 14-pin SOIC (D) package, 3.9 mm wide, 1.75 mm maximum height, RoHS-compliant with NiPdAu lead finish, moisture sensitivity level 1, and tape-and-reel packaging (2500 units per reel).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LS73ADR, SN74LS73ADRG4 shares identical functionality and performance but carries legacy G4 suffix indicating green-processed, Pb-free-compliant marking; versus SN74LS112N, it omits preset capability-reducing pin count and simplifying control logic where only asynchronous reset is needed.

Availability

SN74LS73ADRG4 is available at Aetrix Electronics and suitable for industrial counter modules, digital test equipment, legacy system repair, and education & lab training requiring stable component supply and long-term obsolescence management.

Supply support for SN74LS73ADRG4 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 U.S.-based semiconductor company founded in 1930, specializing in analog, embedded processing, and logic ICs with broad industrial, automotive, and consumer design support infrastructure.

The SN74LS73ADRG4 belongs to TI's legacy 74LS logic family, designed specifically for backward-compatible replacement of 1970s–1980s TTL systems while maintaining strict electrical and timing equivalence across temperature and supply variations.

FAQ

Is SN74LS73ADRG4 pin-compatible with SN74LS73AN?

Yes, SN74LS73ADRG4 and SN74LS73AN share identical 14-pin SOIC and PDIP footprints respectively, but differ in package type: SN74LS73ADRG4 uses SOIC-D while SN74LS73AN uses PDIP-N. They are electrically identical and functionally interchangeable when board layout accommodates the package change. SN74LS73ADRG4 is not a drop-in replacement on a PDIP footprint without redesign.

What is the maximum clock frequency supported by SN74LS73ADRG4?

The SN74LS73ADRG4 does not specify a maximum clock frequency directly, but its 15 ns maximum propagation delay and 5 ns minimum clock pulse width constrain practical operation to approximately 30 MHz in ideal conditions. Real-world designs typically limit to 15–20 MHz to maintain setup/hold timing margins across voltage and temperature extremes.

Does SN74LS73ADRG4 include preset functionality?

No, SN74LS73ADRG4 provides only asynchronous clear (CLR̅) inputs and lacks preset (PRE̅) inputs. Each flip-flop can be forced to Q = 0 asynchronously but cannot be set to Q = 1 without external combinational logic. For preset capability, consider SN74LS112N instead.

Can SN74LS73ADRG4 drive CMOS inputs directly?

SN74LS73ADRG4 outputs meet TTL voltage levels (VOH ≈ 2.7 V min, VOL ≈ 0.5 V max), which fall outside standard CMOS VIH/VIL thresholds. Direct driving of 74HC or 74AHC inputs is unreliable; a TTL-to-CMOS buffer or resistor-based level translator is required for robust interfacing.

What is the meaning of the 'G4' suffix in SN74LS73ADRG4?

The 'G4' suffix in SN74LS73ADRG4 indicates Texas Instruments' green-processed, lead-free-compliant marking designation-denoting RoHS compliance, NiPdAu lead finish, and adherence to TI's environmental manufacturing standards introduced in the early 2000s. It does not alter electrical or timing specifications versus non-G4 variants like SN74LS73ADR.