Texas Instruments SN74HC112DT

Overview

SN74HC112DT from Texas Instruments is a dual J-K negative-edge-triggered flip-flop with independent preset (PRE) and clear (CLR) inputs, operating across 2V–6V supply range, delivering 13ns typical propagation delay at 6V, ±4mA output drive at 5V, and 40μA max ICC - used in LED display timing control and I/O expansion logic circuits.

For engineers reviewing the SN74HC112DT datasheet, SN74HC112DT pinout, SN74HC112DT application, or SN74HC112DT equivalent, key selection considerations include negative-edge clock triggering, asynchronous PRE/CLR behavior, guaranteed setup/hold timing at 2V–6V, and SOIC-16 package compatibility with industrial-grade thermal performance (RθJA = 117.2°C/W).

Technical Context

The SN74HC112DT implements two independent J-K flip-flops sharing no internal coupling; each responds solely to its own CLK, J, K, PRE, and CLR signals. Clock triggering occurs at a defined voltage threshold on the falling edge-not dependent on CLK fall time-enabling robust synchronization in noisy environments.

Asynchronous PRE and CLR override all other inputs with priority, forcing Q to high or low regardless of clock or data state. When both are high, data transfer occurs only on the negative-going CLK edge, with setup time as low as 17ns (6V) and zero hold time requirement.

Key Specifications

Pinout & Package

SN74HC112DT is housed in a 16-pin SOIC (D) package measuring 9.9mm × 6.0mm (body size 9.9mm × 3.9mm), with standard 1.27mm pitch and gull-wing leads compatible with automated SMT assembly and IPC-7351B footprint guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74HC112DT, SN74HC76N requires redesign due to opposite clock edge and active-high controls, while 74HC112D offers true functional and mechanical equivalence with ongoing availability - making it the only viable drop-in replacement for new designs and BOM refreshes.

Availability

SN74HC112DT is available at Aetrix Electronics and suitable for LED display multiplexing, I/O expansion, and motor driver enable sequencing requiring stable component supply across industrial temperature ranges and long-life product programs.

Supply support for SN74HC112DT 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 building blocks.

The SN74HC112DT belongs to TI's 74HC logic family - engineered for low-power, wide-voltage CMOS operation in industrial control, communications infrastructure, and display subsystems where timing precision and noise immunity are critical.

FAQ

What is the maximum clock frequency supported by the SN74HC112DT?

The SN74HC112DT supports up to 24MHz maximum clock frequency at 6V supply, as specified in the switching characteristics table under fmax (6V, SN74HC112). At 4.5V, the limit drops to 20MHz, and at 2V it is 4MHz. These values assume CL = 50pF load and operation within recommended conditions; actual system-level frequency may be lower due to PCB trace capacitance and drive strength limitations.

Does the SN74HC112DT support 3.3V operation?

Yes, the SN74HC112DT fully supports 3.3V operation within its 2V–6V supply range. At 3.3V, it delivers guaranteed VIH ≥ 2.31V and VIL ≤ 0.99V per the recommended operating conditions, with typical propagation delay of ~18ns and output drive of ±3.2mA - making it interoperable with standard 3.3V CMOS logic families without level translation.

Can the SN74HC112DT be used as a divide-by-2 counter?

Yes, the SN74HC112DT can function as a divide-by-2 counter by connecting J and K inputs high on either flip-flop. On each negative clock edge, the output toggles state - producing a 50% duty-cycle square wave at half the input clock frequency. This configuration requires no external components and leverages the device's inherent toggle mode defined in the function table.

What is the purpose of the PRE and CLR pins on the SN74HC112DT?

The PRE (pin 1 and 15) and CLR (pin 2 and 16) pins on the SN74HC112DT provide asynchronous set and reset functionality. A low signal on PRE forces Q = H and Q̅ = L; a low on CLR forces Q = L and Q̅ = H - both overriding clock and data inputs. These pins enable immediate state initialization or fault recovery without waiting for the next clock edge, critical for safety-critical or startup-reset sequences.

Is the SN74HC112DT pin-compatible with older 74LS112 devices?

No, the SN74HC112DT is not pin-compatible with the bipolar 74LS112. Although both are dual J-K flip-flops in 16-pin packages, the SN74HC112DT uses SOIC (D) packaging with different pin assignments - notably, VCC is on pin 16 and GND on pin 8, whereas 74LS112 places VCC on pin 14 and GND on pin 7. Electrical differences (CMOS vs. TTL input thresholds, drive strength, and power consumption) also preclude direct substitution without circuit validation.