Texas Instruments SN74S112ADR

Overview

SN74S112ADR from Texas Instruments is a dual J-K negative-edge-triggered flip-flop IC used for synchronous logic control and data storage in digital systems. It features complementary Q and Q̅ outputs, independent preset and clear inputs, and operates across 0°C to 70°C with typical propagation delay of 5 ns at VCC = 5 V. It is commonly deployed in clocked state machines, counters, and register files within industrial control and test equipment.

For engineers reviewing the SN74S112ADR datasheet, SN74S112ADR pinout, SN74S112ADR application, or SN74S112ADR equivalent, this page delivers verified functional identity, SOIC-16 package details, timing parameters, real-world use cases, and validated alternative options aligned with TI's official specifications.

Technical Context

The SN74S112ADR implements two independent J-K flip-flops with asynchronous active-low preset (PR̅) and clear (CLR̅) inputs, each triggered on the falling edge of the clock (CLK). Its Schottky-clamped TTL architecture ensures fast switching and noise immunity.

Each flip-flop supports toggle, set, reset, and hold functions via J/K input combinations. The device requires VCC = 4.75 V to 5.25 V and draws ICC = 24 mA max under full load, with guaranteed fan-out of 20 LS-TTL loads.

Key Specifications

Pinout & Package

SN74S112ADR is housed in a 16-pin SOIC (D) package measuring 10.4 mm × 7.4 mm × 2.0 mm max height, RoHS-compliant with NiPdAu lead finish and moisture sensitivity level 1 (unlimited floor life at ≤30°C/60% RH).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LS112ADR and SN74F112DR, the SN74S112ADR strikes a balance: faster than LS but more power-efficient than F, making it optimal for mid-speed industrial logic where reliability and timing margin are prioritized over extreme frequency or ultra-low power.

Availability

SN74S112ADR is available at Aetrix Electronics and suitable for industrial counter systems, digital test equipment, legacy bus interface logic, and power sequencing control requiring stable component supply and long-term manufacturability.

Supply support for SN74S112ADR 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 90 years of innovation in high-reliability digital components.

The SN74S112ADR belongs to TI's 74S logic family, engineered for high-speed commercial and industrial applications where consistent timing, robust noise immunity, and direct TTL interoperability are essential.

FAQ

What is the maximum clock frequency supported by SN74S112ADR?

The SN74S112ADR does not specify a maximum clock frequency in its datasheet; instead, it guarantees a maximum propagation delay of 5 ns (tPLH/tPHL) under standard conditions. This implies reliable operation up to approximately 100 MHz in well-designed circuits with controlled trace lengths and proper termination. Actual usable frequency depends on board layout, load capacitance, and power supply stability - always verify timing margins using worst-case setup/hold analysis for the SN74S112ADR in your specific design.

Does SN74S112ADR support synchronous preset and clear?

No, the SN74S112ADR implements only asynchronous active-low preset (PR̅) and clear (CLR̅) inputs - they override clock and J/K inputs immediately upon assertion, regardless of clock state. Synchronous control requires external gating logic or selection of a different family (e.g., 74ACT series). This behavior is inherent to the SN74S112ADR's architecture and confirmed in TI's official datasheet.

Can SN74S112ADR be used as a divide-by-2 counter?

Yes, the SN74S112ADR can be configured as a divide-by-2 counter by connecting J = K = VCC and feeding Q̅ back to CLK of the same section. This creates a toggle mode where each falling clock edge flips the output state, yielding a 50% duty cycle square wave at half the input frequency. This configuration is explicitly supported and documented for the SN74S112ADR in TI application notes.

Is SN74S112ADR pin-compatible with SN74LS112ADR?

Yes, the SN74S112ADR and SN74LS112ADR share identical SOIC-16 pinouts, terminal assignments, and functional block diagrams. However, they differ electrically: SN74S112ADR offers faster propagation (5 ns vs. 15 ns), higher drive current, and greater power consumption. Direct substitution is possible in most layouts, but verify timing closure and power delivery for the SN74S112ADR's increased ICC.

What is the recommended bypass capacitor for SN74S112ADR?

Texas Instruments recommends a 0.1 µF ceramic capacitor placed as close as possible between Pin 16 (VCC) and Pin 8 (GND) for the SN74S112ADR. This minimizes high-frequency supply noise induced by simultaneous output switching. For systems with multiple SN74S112ADR devices or heavy transient loads, add a bulk 4.7 µF–10 µF tantalum or aluminum electrolytic capacitor nearby on the same 5-V rail.