Texas Instruments SN74F112NG4

Overview

SN74F112NG4 from Texas Instruments is a dual negative-edge-triggered J-K flip-flop with independent preset and clear inputs, operating at 5 V supply, supporting up to 100 MHz clock frequency, with 4.5 ns setup time and 0 ns hold time, used in synchronous logic control and state-machine sequencing in industrial digital systems.

For engineers reviewing the SN74F112NG4 datasheet, SN74F112NG4 pinout, SN74F112NG4 application, or SN74F112NG4 equivalent, this page delivers verified functional identity, validated DIP-16 pin mapping, confirmed timing parameters (t_su = 4 ns, t_PLH = 6.5 ns), and two field-validated alternative parts for legacy TTL logic replacement.

Technical Context

The SN74F112NG4 implements two fully independent J-K flip-flops sharing no internal signal paths; each features asynchronous active-low PRE and CLR inputs that override clocked operation, and operates on the falling edge of CLK only. Its logic is strictly TTL-compatible with VIH = 2 V and VIL = 0.8 V.

It uses standard bipolar F-type TTL circuitry - not CMOS or BiCMOS - resulting in ICC = 19 mA typical at 5.5 V, VOL = 0.5 V at 20 mA sink, and propagation delays under 7.5 ns across temperature (0°C to 70°C). No internal pull-ups, Schmitt triggers, or bus-hold circuits are present.

Key Specifications

Pinout & Package

SN74F112NG4 is supplied in a 16-pin plastic dual in-line package (PDIP-N), 300-mil width, with 0.1-inch lead pitch and through-hole mounting. Pin 1 is marked by a notch or dot at the top-left corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74F112NG4, SN74LS112N trades 2.5× lower speed for 90% less supply current and improved noise rejection, while SN74HC112N sacrifices speed and TTL compatibility for voltage scalability and near-zero static power - neither is pin-compatible without logic-level adaptation.

Availability

SN74F112NG4 is available at Aetrix Electronics and suitable for industrial control sequencing, digital test equipment, legacy system repair, and education & lab training requiring stable component supply and long-term obsolescence mitigation.

Supply support for SN74F112NG4 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 solutions for industrial, automotive, and communications markets.

The SN74F112NG4 belongs to TI's legacy 74F TTL logic family, designed specifically for high-speed, noise-tolerant digital control in commercial-grade systems where reliability and interoperability with existing 74-series infrastructure were paramount.

FAQ

Is SN74F112NG4 pin-compatible with SN74F112N?

Yes, SN74F112NG4 is functionally and physically identical to SN74F112N - both are 16-pin PDIP packages with identical pinout, electrical specifications, and timing behavior. The "G4" suffix denotes TI's green packaging standard (lead-free, RoHS-compliant finish), but does not alter pin assignment or logic function. SN74F112NG4 maintains full drop-in compatibility with legacy SN74F112N designs.

What is the maximum clock frequency supported by SN74F112NG4 across its full temperature range?

The SN74F112NG4 guarantees operation up to 100 MHz over its full rated temperature range of 0°C to 70°C. This value is specified in the "timing requirements" table of the official datasheet (SDFS048A, Rev. October 1993) under "fclock MAX" at TA = MIN to MAX. At 25°C, it can reach 110 MHz, but system-level timing must be validated at 100 MHz for robust commercial deployment.

Does SN74F112NG4 support asynchronous toggle mode?

No - SN74F112NG4 does not have a dedicated toggle mode input. However, it achieves toggle behavior when both J and K inputs are held high (J = K = H); on each negative clock edge, the output complements its previous state. This is explicitly confirmed in the FUNCTION TABLE and description sections of the datasheet, and requires no additional control logic.

Can SN74F112NG4 operate from a 3.3 V supply?

No, SN74F112NG4 is a strict 5 V TTL device and is not characterized or guaranteed for operation below 4.5 V. Its input thresholds (VIH = 2.0 V, VIL = 0.8 V) and output drive (VOH ≥ 2.5 V at –1 mA) assume a 5 V rail. Attempting 3.3 V operation results in undefined logic levels, excessive propagation delay, and potential failure to meet setup/hold timing - use SN74HC112N instead for 3.3 V systems.

What is the purpose of the "inactive-state setup time" (tsu) parameter for PRE/CLR in SN74F112NG4?

The inactive-state setup time (tsu = 4 ns min) specifies how long PRE and CLR must remain high before the next CLK↓ edge to ensure predictable sampling of J/K data. If either input returns high too close to the clock edge, the flip-flop may enter a metastable or non-deterministic state. This parameter - also called "recovery time" - is critical for reliable transition from asynchronous reset/preset back to synchronous operation in SN74F112NG4.