Texas Instruments CD74HC243M96G4

Overview

CD74HC243M96G4 from Texas Instruments is a high-speed CMOS quad-bus transceiver with three-state outputs, designed for bidirectional asynchronous communication between data buses. It operates from 2 V to 6 V, delivers 7 ns typical propagation delay (A↔B) at VCC = 5 V/CL = 15 pF, supports -55°C to +125°C temperature range, and drives up to 15 LSTTL loads - enabling robust bus interfacing in industrial control backplanes.

For engineers reviewing the CD74HC243M96G4 datasheet, CD74HC243M96G4 pinout, CD74HC243M96G4 application, or CD74HC243M96G4 equivalent, this page provides verified functional modes, SOIC-14 package dimensions, truth-table–driven direction control via OEA/OEB, and validated alternatives for bus isolation and level-shifting designs requiring wide-voltage tolerance and low-power CMOS compatibility.

Technical Context

The CD74HC243M96G4 implements four independent noninverting bidirectional channels, each controlled by shared OEA and OEB inputs that jointly determine data flow direction (A→B or B→A) and three-state output enable/disable state. Its silicon-gate CMOS architecture ensures rail-to-rail input thresholds and low ICC (≤160 µA max over full temperature range).

It features buffered inputs, balanced propagation delay and transition times, and high noise immunity (NIL/NIH = 30% of VCC at 5 V). Unlike HCT variants, the HC-type logic accepts 2 V–6 V supply and exhibits CMOS-compatible input leakage (±1 µA max), making it suitable for mixed-voltage system interconnects without external level shifters.

Key Specifications

Pinout & Package

CD74HC243M96G4 is housed in a 14-pin SOIC (D) package with 8.65 mm × 3.90 mm body size, 1.75 mm max height, and 1.27 mm lead pitch. Pin 1 is located at the top-left corner with notch or beveled edge marking.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad-bus transceiver applications.

Compared with CD74HC243M96G4, SN74LVC243APWR offers faster speed and higher drive at 3.3 V but sacrifices voltage flexibility and temperature range; CD74HCT243M96G4 retains identical form-factor and mechanical fit while ensuring LSTTL input recognition - making it the only true functional substitute in legacy 5 V systems.

Availability

CD74HC243M96G4 is available at Aetrix Electronics and suitable for industrial backplane interconnect, automotive ECU diagnostics, and test equipment bus expansion requiring stable component supply across extended temperature and mixed-voltage environments.

Supply support for CD74HC243M96G4 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 connectivity technologies with over 90 years of innovation in high-reliability IC design.

CD74HC243M96G4 belongs to TI's CDx4HC logic family, engineered for robust bidirectional bus interfacing in harsh environments - emphasizing wide voltage operation, extended temperature resilience, and low-power CMOS efficiency.

FAQ

What is the supply voltage range supported by CD74HC243M96G4?

CD74HC243M96G4 supports a supply voltage range of 2 V to 6 V, allowing seamless integration into mixed-voltage systems including 3.3 V and 5 V buses. This wide range eliminates the need for external level-shifting circuitry and ensures compatibility with both legacy and modern logic families, as confirmed in Section 5.2 of the TI datasheet SCHS168E.

How does the OEA and OEB pin configuration control data direction in CD74HC243M96G4?

In CD74HC243M96G4, OEA and OEB are active-low control inputs that jointly define direction and three-state behavior: when OEA = L and OEB = H, data flows B→A; when OEA = H and OEB = L, data flows A→B; when both are high, all outputs enter high-Z; when both are low, outputs are enabled but direction is undefined per truth table. This dual-control scheme prevents bus contention in multi-master systems.

Is CD74HC243M96G4 compatible with LSTTL input logic levels?

No - CD74HC243M96G4 is an HC-type device with CMOS input thresholds (VIH = 3.15 V min at VCC = 4.5 V), not LSTTL-compatible. For LSTTL input compatibility (VIH = 2 V min, VIL = 0.8 V max), use the pin-compatible CD74HCT243M96G4 variant instead. This distinction is explicitly defined in Sections 1 and 5.4 of the datasheet.

What is the maximum operating temperature for CD74HC243M96G4?

CD74HC243M96G4 is rated for continuous operation from -55°C to +125°C, as specified in Section 5.2 (Recommended Operating Conditions) and validated across all electrical parameters in Table 5.4. This makes it suitable for under-hood automotive, industrial motor control, and aerospace applications where thermal extremes are routine.

Does CD74HC243M96G4 require external bypass capacitors, and if so, what value?

Yes - TI recommends a 0.1 µF ceramic bypass capacitor placed as close as possible to the VCC pin (Pin 12) and GND (Pin 7) to suppress supply noise and ensure stable high-speed switching. Section 8 of the datasheet states this is mandatory for reliable operation, especially when driving large bus capacitances or operating near maximum frequency limits.