NXP Semiconductors 74HCT7030D,118

Overview

74HCT7030D,118 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 supports up to 29 MHz shift-in/shift-out operation at 5 V, delivers 33 MHz typical burst-mode data rates, and enables cascading for expanded word capacity. It is used in high-speed A/D output buffering and video timebase correction systems.

For engineers reviewing the 74HCT7030D,118 datasheet, 74HCT7030D,118 pinout, 74HCT7030D,118 application, or 74HCT7030D,118 equivalent, this page provides verified functional architecture, timing-critical parameters (e.g., SI-to-DIR tPLH = 29 ns, SO-to-Qn tPHL = 46 ns), cascade-ready flag behavior, and real-world use cases including disc controller data staging and bit-rate smoothing.

Technical Context

The 74HCT7030D,118 implements a Si-gate CMOS FIFO with independent shift-in (SI) and shift-out (SO) controls, enabling fully asynchronous read/write operations. Its DIR and DOR flags provide deterministic status signaling-DIR = HIGH indicates empty input stage ready for data; DOR = HIGH confirms valid data present at Q0–Q8 outputs.

It supports three operational modes: flag-gated (safe, 26–29 MHz max), high-speed burst (up to 35 MHz), and cascaded (25 MHz typical for two devices). The device features ripple-through propagation (SI→DOR: 0.9 µs typ.) and bubble-up delay (SO→DIR: 1.2 µs typ.), both critical for multi-FIFO synchronization in expanded memory configurations.

Key Specifications

Pinout & Package

74HCT7030D,118 is housed in a 28-pin Small Outline (SO28) package per JEDEC MS-013AC, with GND on pins 1, 2, and 14, and V_CC on pin 28. Input and output pins are arranged in mirrored layout (D0–D8 on pins 5–13; Q0–Q8 on pins 16–24) to simplify PCB routing in expanded FIFO arrays.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 74HCT7030D,118, the 74HC7030D,653 trades interface compatibility for lower quiescent current, while the SN74ACT7030N offers superior speed but lacks verified cascade timing - making 74HCT7030D,118 the only option with documented 25 MHz cascaded operation and full flag interoperability.

Availability

74HCT7030D,118 is available at Aetrix Electronics and suitable for high-speed disc controllers, video timebase correction circuits, and A/D output buffering requiring stable component supply across industrial and broadcast equipment lifecycles.

Supply support for 74HCT7030D,118 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, formerly Philips Semiconductors, designs high-reliability logic and interface ICs for industrial, automotive, and communications infrastructure.

The 74HCT7030D,118 belongs to the 74HCT logic family - engineered for TTL-compatible interfacing in mixed-signal systems where robust noise immunity and predictable timing at 5 V are essential.

FAQ

What is the maximum guaranteed clock frequency for 74HCT7030D,118 when using DIR and DOR flags for handshaking?

The 74HCT7030D,118 guarantees 29 MHz maximum clock frequency for SI and SO operations under flag-gated conditions at V_CC = 4.5 V and T_amb = +25 °C. This value drops to 26 MHz over the full −40 °C to +85 °C industrial temperature range. Operation above this frequency requires burst-mode timing, where flags are ignored and pulse widths must meet minimum specifications (SI HIGH/LOW ≥12 ns, SO HIGH/LOW ≥15 ns).

How does the 74HCT7030D,118 handle cascading for increased word depth, and what is the verified performance limit?

The 74HCT7030D,118 supports seamless cascading via DIR and DOR flag chaining - DOR from one device drives SI of the next, and DIR from the second feeds back to SO of the first. Philips documentation verifies 25 MHz typical operation for two cascaded 74HCT7030D,118 devices forming a 128-word × 9-bit FIFO, with inter-device timing governed by flag pulse widths and ripple-through delays.

Can unused data input pins (D0–D8) on the 74HCT7030D,118 be left floating, or must they be terminated?

Unused data input pins on the 74HCT7030D,118 must not be left floating. Per Philips specification, they must be tied to either V_CC or GND to define logic state and prevent undefined operation or excessive current draw. This termination also enables bit-width reduction - e.g., tying D8 to V_CC configures the device as an 8-bit × 64-word FIFO.

What is the function of the master-reset (MR) input on the 74HCT7030D,118, and how does it affect DIR and DOR flags?

The MR input on the 74HCT7030D,118 is an asynchronous active-LOW signal that clears all internal control logic and invalidates stored data. Upon MR assertion, DIR is forced HIGH (indicating input stage ready) and DOR is forced LOW (indicating output stage empty). The Q0–Q8 outputs retain their last valid state or power-up random state until new data is shifted out.

Is the 74HCT7030D,118 pin-compatible with other members of the 74HC/HCT7030 family, such as the 74HC7030D?

Yes, the 74HCT7030D,118 is pin-compatible with all variants in the 74HC/HCT7030 family, including 74HC7030D and 74HCT7030N. All share identical SO28 pinout, terminal functions, and electrical interface definitions. The only differences are input threshold voltages (TTL-compatible for HCT, CMOS for HC) and AC timing parameters - substitution requires verification of system-level voltage and timing margins.