Texas Instruments CD54AC112F3A

Overview

CD54AC112F3A from Texas Instruments is a dual J-K negative-edge-triggered flip-flop with independent preset and clear inputs, operating across 1.5 V to 5.5 V supply range, delivering 114 MHz max clock frequency at 5 V, ±24 mA output drive, and MIL-PRF-38535 qualified performance for aerospace and defense systems requiring radiation-tolerant logic sequencing.

For engineers reviewing the CD54AC112F3A datasheet, CD54AC112F3A pinout, CD54AC112F3A application, or CD54AC112F3A equivalent, key selection criteria include negative-edge clocking behavior, simultaneous asynchronous PRE/CLR control per flip-flop, guaranteed hold time of 0 ns, SCR-latchup immunity, and operation over –55°C to +125°C.

Technical Context

This device implements two fully independent CMOS J-K flip-flops sharing only VCC and GND rails. Each section features separate J, K, CLK, PRE, CLR, Q, and Q̅ terminals, enabling discrete toggle, set/reset, or data latch functions without inter-stage coupling.

Triggering occurs exclusively on the falling edge of CLK; PRE and CLR are active-low asynchronous controls overriding clocked behavior. The design enforces zero hold time (th = 0 ns) and supports direct J=K=HIGH configuration for toggle mode - verified across all voltage and temperature ranges.

Key Specifications

Pinout & Package

CD54AC112F3A uses a 16-pin Ceramic Dual In-line Package (CDIP) with hermetic sealing and gold-plated leads, optimized for high-reliability, long-lifetime applications in vacuum or extreme thermal cycling environments.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CD74AC112M and SN54ACT112J, the CD54AC112F3A uniquely combines hermetic CDIP packaging, full MIL-PRF-38535 Class B qualification, and AC-series low-power high-speed operation - making it irreplaceable in launch vehicle avionics and nuclear instrumentation where reliability trumps form-factor or cost.

Availability

CD54AC112F3A is available at Aetrix Electronics and suitable for avionics sequencing, satellite command decoding, tactical radio modem control, and nuclear instrumentation systems requiring stable component supply across extended product lifecycles.

Supply support for CD54AC112F3A 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 high-reliability logic solutions, with decades of heritage in aerospace-grade component development.

The CD54AC112F3A belongs to TI's military-grade AC logic family, engineered specifically for high-speed, low-power, radiation-resilient digital control in mission-critical defense and space platforms.

FAQ

What is the maximum clock frequency supported by CD54AC112F3A at 5 V?

The CD54AC112F3A supports a maximum clock frequency of 114 MHz at VCC = 5 V ± 0.5 V across the full –55°C to +125°C operating range, as specified in the switching characteristics table of the SCHS325 datasheet. This value reflects worst-case timing under load (CL = 50 pF) and guarantees deterministic operation in high-speed control loops without derating.

Does CD54AC112F3A require external pull-up resistors on PRE and CLR inputs?

No, CD54AC112F3A does not require external pull-up resistors on PRE or CLR inputs. These inputs are internally biased and function correctly when left unconnected only if tied to VCC or GND per TI application note SCBA004; however, best practice mandates explicit termination to avoid floating states that could induce metastability or unintended toggling during power-up or EMI events.

Is CD54AC112F3A pin-compatible with CD74AC112E or CD74AC112M?

Yes, CD54AC112F3A is pin-compatible with CD74AC112E (PDIP-16) and CD74AC112M (SOIC-16) - all share identical 16-pin assignments and signal definitions per the logic diagram and pinout drawing in SCHS325. However, package dimensions, thermal profiles, and qualification levels differ significantly, so mechanical and reliability validation is required before substitution.

What is the meaning of "F3A" in CD54AC112F3A?

The "F3A" suffix in CD54AC112F3A denotes Texas Instruments' standardized military-grade package code: "F" indicates Ceramic Dual In-line Package (CDIP), "3" specifies lead finish (gold), and "A" identifies the revision level and screening grade compliant with MIL-PRF-38535 Class B requirements for space applications.

Can CD54AC112F3A operate reliably at 1.5 V supply voltage?

Yes, CD54AC112F3A is fully specified to operate at 1.5 V supply voltage, with validated parameters including 8 MHz max clock frequency, 129 ns propagation delay, and 30% VCC noise immunity. Its AC logic architecture maintains rail-to-rail swing and balanced delays even at minimum VCC, enabling ultra-low-power operation in battery-constrained avionics subsystems.