NXP Semiconductors 74HCT7030D,112

Overview

74HCT7030D,112 from NXP Semiconductors (formerly Philips) is a 9-bit × 64-word synchronous/asynchronous FIFO register with 3-state outputs, master-reset (MR), output-enable (OE), and dual status flags (DIR/DOR). It delivers 29 MHz max clock frequency (HCT), 40 ns SO-to-Qn propagation delay, and supports cascading for 128-word expansion. It serves as a high-speed data buffer in video timebase correction and A/D output staging.

For engineers reviewing the 74HCT7030D,112 datasheet, 74HCT7030D,112 pinout, 74HCT7030D,112 application, or 74HCT7030D,112 equivalent, key selection criteria include DIR/DOR flag timing behavior, 3-state output enable/disable delays (53 ns typ.), ripple-through vs. bubble-up latency, cascaded word-expansion capability, and HCT-level TTL-compatible input thresholds at 5 V supply.

Technical Context

The 74HCT7030D,112 implements a dual-control FIFO architecture with independent shift-in (SI) and shift-out (SO) edge-triggered inputs: SI is LOW-to-HIGH active for loading, SO is HIGH-to-LOW active for unloading. Its DIR flag asserts HIGH when input stage is empty and ready; DOR asserts HIGH only when valid data resides at Q0–Q8 outputs - not merely queued.

It supports three operational modes: asynchronous flag-driven transfer (using DIR/DOR handshaking), synchronous burst mode (up to 26 MHz with no flag dependency), and cascaded configuration (two devices yield 128 × 9-bit capacity with inter-FIFO flag chaining). All 9 data inputs (D0–D8) and outputs (Q0–Q8) are unweighted and bidirectionally assignable as MSB/LSB.

Key Specifications

Pinout & Package

74HCT7030D,112 is housed in a 28-pin SOIC (Small Outline Integrated Circuit) package per JEDEC MS-012, with 300 mil body width and 1.27 mm pitch. Pin 14 is dedicated GND; pins 1 and 2 are auxiliary GND connections - all three must be connected to system ground with no current flow between them.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74HCT7030D,112, the 74HC7030D,653 offers higher speed but requires stricter input voltage margins, while SN74ACT2227N provides wider data path at cost of flag protocol incompatibility - neither matches the integrated DIR/DOR handshaking and cascading simplicity of the original.

Availability

74HCT7030D,112 is available at Aetrix Electronics and suitable for high-speed disc/tape controllers, video timebase correction circuits, A/D output buffering, and digital filter I/O formatting requiring stable component supply across extended production lifecycles.

Supply support for 74HCT7030D,112 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

NXP Semiconductors, headquartered in Eindhoven, Netherlands, designs high-reliability logic and interface ICs for industrial, automotive, and communications infrastructure markets.

The 74HCT7030D,112 belongs to NXP's legacy 74HCT logic family - engineered specifically for TTL-compatible 5 V systems requiring robust noise immunity, low-power CMOS efficiency, and deterministic FIFO timing in real-time data buffering applications.

FAQ

What is the operating voltage range for the 74HCT7030D,112?

The 74HCT7030D,112 operates within a supply voltage range of 4.5 V to 5.5 V. Its HCT logic family ensures TTL-compatible input thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V) across this range, enabling direct interfacing with legacy 5 V TTL devices without level shifting. Operation outside this range risks undefined behavior or permanent damage.

How does the DIR flag behave during reset and data loading in the 74HCT7030D,112?

Upon assertion of MR (LOW), the 74HCT7030D,112 clears internal state and sets DIR = HIGH immediately, signaling readiness to accept data. When SI goes HIGH, DIR drops LOW to indicate the input stage is busy loading; it returns HIGH only after SI goes LOW and the FIFO has space. DIR remains LOW if the FIFO is full - it never pulses HIGH during overflow attempts.

Can the 74HCT7030D,112 be used in a 5-bit configuration, and how is that implemented?

Yes, the 74HCT7030D,112 supports bit-width reduction down to 1-bit. To configure as 5-bit, tie D4–D8 and Q4–Q8 to VCC or GND (per datasheet guidance), leaving D0–D3 and Q0–Q3 active. Unused output pins (Q4–Q8) must remain open-circuit; unused inputs (D4–D8) may be tied to either rail. The DIR/DOR flags and timing remain fully functional.

What is the minimum pulse width required for reliable SO operation in the 74HCT7030D,112?

The 74HCT7030D,112 requires a minimum SO pulse width of 9 ns (HIGH or LOW) at VCC = 4.5 V and Tamb = +25 °C. At temperature extremes (−40 °C to +125 °C), the guaranteed minimum widens to 26 ns. Pulses narrower than specification risk incomplete bubble-up action, causing DOR to remain LOW or DIR to fail assertion.

Is the 74HCT7030D,112 pin-compatible with the 74HC7030D,653, and what are the practical implications?

Yes, the 74HCT7030D,112 and 74HC7030D,653 share identical pinout, package (28-pin SOIC), and functional block diagram. However, their AC characteristics differ: HCT offers TTL-compatible inputs and 29 MHz max frequency, while HC delivers 33 MHz but requires VCC-referenced thresholds. Firmware and layout are interchangeable, but timing margins and input drive requirements must be re-validated.