Texas Instruments CD74HCT670M96G4

Overview

CD74HCT670M96G4 from Texas Instruments is a 4-word × 4-bit high-speed CMOS register file with simultaneous independent read/write capability, three-state outputs, buffered inputs, and operation across -55°C to +125°C. It supports LSTTL-compatible input thresholds (VIL ≤ 0.8 V, VIH ≥ 2.0 V), 4.5–5.5 V supply, and enables real-time data buffering in digital control systems.

For engineers reviewing the CD74HCT670M96G4 datasheet, CD74HCT670M96G4 pinout, CD74HCT670M96G4 application, or CD74HCT670M96G4 equivalent, key selection criteria include simultaneous read/write timing (tLATCH = 25–38 ns), output enable/disable times (tPZL/tPLZ = 16–57 ns at 5 V), three-state bus interface compatibility, and SOIC-16 packaging for space-constrained embedded logic designs.

Technical Context

The CD74HCT670M96G4 implements a synchronous register file architecture with dual address decoders (WA0/WA1 for write, RA0/RA1 for read), enabling concurrent access to separate 4-bit words without arbitration. Its HCT logic family ensures direct interfacing with legacy TTL systems while maintaining CMOS power efficiency.

Write operations are edge-triggered by WE low, latching data only when WA0/WA1 are stable; read operations respond asynchronously to RE low and RA0/RA1, with outputs entering high-impedance state when RE is high. All inputs are buffered, and outputs drive up to 15 LSTTL loads with balanced propagation delay (tPHL/tPLH = 40–53 ns for read).

Key Specifications

Pinout & Package

CD74HCT670M96G4 is housed in a 16-pin SOIC (Small Outline Integrated Circuit) package with 1.27 mm pitch, JEDEC MS-012 compliant, moisture sensitivity level 1 (260°C reflow compatible), and tape-and-reel delivery (2500 units per reel).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar register file applications.

Compared with CD74HCT670M96G4, CD74HC670M96 trades LSTTL compatibility for wider voltage operation and lower static current, while SN74ACT670N delivers superior speed and drive at the cost of temperature range and higher quiescent power-making CD74HCT670M96G4 optimal for ruggedized 5 V systems requiring guaranteed TTL interoperability.

Availability

CD74HCT670M96G4 is available at Aetrix Electronics and suitable for industrial automation, automotive body electronics, and test equipment requiring stable component supply, long-term lifecycle support, and traceable sourcing under extended temperature conditions.

Supply support for CD74HCT670M96G4 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 decades of heritage in high-reliability logic families.

The CD74HCT670M96G4 belongs to TI's High-Speed CMOS Logic (HCT) register file product line, designed specifically for deterministic, low-latency data staging in mixed-technology digital systems requiring seamless TTL-to-CMOS bridging.

FAQ

What is the maximum operating frequency supported by the CD74HCT670M96G4?

The CD74HCT670M96G4 does not specify a maximum clock frequency directly, but its read propagation delay is 40–53 ns (CL = 50 pF), and write setup/hold times are 12–27 ns. For reliable operation, system clock periods should exceed 100 ns (10 MHz), allowing margin for address decoding and bus settling. The device is optimized for asynchronous address-controlled access rather than synchronous clocked operation.

Can the CD74HCT670M96G4 be used with a 3.3 V microcontroller?

No-the CD74HCT670M96G4 requires a 4.5–5.5 V supply and is specified only for LSTTL-compatible inputs (VIL ≤ 0.8 V, VIH ≥ 2.0 V). While 3.3 V logic may meet VIH min under some conditions, it violates the guaranteed input threshold spec and risks unreliable operation. Use CD74HC670M96 for true 3.3 V compatibility.

Does the CD74HCT670M96G4 support true dual-port operation with independent clocks?

No-the CD74HCT670M96G4 supports simultaneous read and write *within the same clock domain*, using shared control signals (WE, RE) and asynchronous address inputs. It lacks separate read/write clocks or arbitration logic; timing depends entirely on setup/hold relationships between WA0/WA1, RA0/RA1, WE, and RE-not independent clock edges.

What is the meaning of the 'G4' suffix in CD74HCT670M96G4?

The 'G4' suffix denotes Texas Instruments' internal assembly and test variant code, indicating a specific wafer fab, assembly site, and test flow. It does not affect electrical specifications or pinout. The base part CD74HCT670M96 is functionally identical; G4 reflects TI's manufacturing revision control and is fully interchangeable in design.

How is bus expansion implemented using multiple CD74HCT670M96G4 devices?

Bus expansion is achieved by connecting D0–D3, Q0–Q3, WA0/WA1, RA0/RA1, WE, and RE in parallel across devices, while using separate chip-select logic (e.g., decoded higher-order address bits) to gate individual RE/WE lines. This creates a wider word (e.g., 8-bit or 16-bit) or deeper memory (up to 512 × 4 bits), preserving simultaneous read/write capability per device.