Texas Instruments CD54ACT109F3A

Overview

CD54ACT109F3A from Texas Instruments is a dual J-K positive-edge-triggered flip-flop with independent preset and clear inputs, designed for high-reliability military-grade logic sequencing. It operates over –55°C to 125°C, delivers ±24-mA output drive, supports 114-MHz max clock frequency at 85°C, and features TTL-voltage-compatible inputs. It is used in radiation-tolerant avionics timing control and synchronous state machines requiring deterministic edge-triggered behavior.

For engineers reviewing the CD54ACT109F3A datasheet, CD54ACT109F3A pinout, CD54ACT109F3A application, or CD54ACT109F3A equivalent, key selection criteria include MIL-PRF-38535 qualification, CDIP-F package thermal robustness, SCR-latchup immunity, and guaranteed propagation delay matching across temperature extremes.

Technical Context

This device implements two fully independent CMOS-based J-K flip-flops sharing only VCC and GND. Each flip-flop responds exclusively to the rising edge of CLK while PRE and CLR override all other inputs asynchronously - enabling hard-wired reset/set in safety-critical sequencers. The internal circuitry uses balanced transistor sizing to minimize skew between Q and Q̅ outputs.

It employs TI's SCR-latchup-resistant ACT process with 2-kV HBM ESD protection and meets MIL-STD-883 Class B requirements. Input thresholds are fixed at VIH = 2 V and VIL = 0.8 V, ensuring compatibility with legacy TTL systems without level-shifting.

Key Specifications

Pinout & Package

CD54ACT109F3A is housed in a hermetically sealed 16-pin Ceramic Dual In-line Package (CDIP-F), rated for high-reliability military environments. Its lead finish is tin-lead (SnPb), and it complies with MIL-STD-883 screening requirements.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CD54ACT109F3A, CD74ACT109M offers easier assembly and RoHS compliance but lacks hermetic sealing and full MIL-PRF-38535 Class V screening; SNJ54ACT109W provides similar packaging and temperature rating but trades off some timing consistency at extreme temperatures for accelerated production availability.

Availability

CD54ACT109F3A is available at Aetrix Electronics and suitable for avionics, defense electronics, and high-temperature industrial control systems requiring stable component supply across extended product lifecycles.

Supply support for CD54ACT109F3A 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 experience in aerospace and defense component development.

CD54ACT109F3A belongs to TI's military-grade ACT logic family, engineered specifically for applications demanding radiation tolerance, wide-temperature operation, and long-term supply assurance in mission-critical systems.

FAQ

What is the maximum clock frequency specification for CD54ACT109F3A at full military temperature range?

The CD54ACT109F3A supports a maximum clock frequency of 100 MHz over the full –55°C to 125°C operating range, verified per MIL-STD-883 test conditions. At the milder –40°C to 85°C range, this increases to 114 MHz. These values reflect guaranteed performance under worst-case voltage (4.5 V) and load (50 pF) conditions as specified in the SCHS327 datasheet.

Does CD54ACT109F3A require external pull-up or pull-down resistors on unused inputs?

Yes - all unused inputs of CD54ACT109F3A must be held at VCC or GND to prevent floating nodes that could cause excessive ICC current or metastability. This requirement is explicitly stated in Note 3 of the datasheet and applies to J, K, CLK, PRE, and CLR pins not actively driven in the application circuit.

Is CD54ACT109F3A pin-compatible with CD74ACT109E or CD74ACT109M?

Yes - CD54ACT109F3A shares identical pinout and logic function with CD74ACT109E (PDIP-16) and CD74ACT109M (SOIC-16), including matching terminal numbering and signal assignments. However, differences in package construction, thermal characteristics, and screening level mean mechanical interchangeability does not imply full functional equivalence in high-reliability contexts.

What does the "F3A" suffix indicate in CD54ACT109F3A?

The "F3A" suffix denotes the specific CDIP-F package variant per TI's packaging nomenclature: "F" identifies the ceramic dual in-line package type, "3" indicates lead finish (SnPb), and "A" signifies compliance with MIL-PRF-38535 Class V screening requirements. This suffix is used internally by TI for traceability and qualification tracking.

Can CD54ACT109F3A be used as a divide-by-two counter?

Yes - CD54ACT109F3A can implement a divide-by-two counter by connecting J=HIGH, K=LOW, and feeding Q̅ back to CLK of the same flip-flop. This configuration leverages its toggle mode, and the device's balanced propagation delays ensure minimal duty-cycle distortion in the resulting square wave output.