NXP Semiconductors 74HC173N,652

Overview

74HC173N,652 from Nexperia is a quad D-type positive-edge-triggered flip-flop with 3-state outputs, master reset, and dual data/output enable controls. It operates at 2–6 V supply, delivers 88 MHz max clock frequency, 17 ns typical CP→Q propagation delay (VCC = 5 V), and functions as a 4-bit parallel-load register in bus-oriented digital systems.

For engineers reviewing the 74HC173N,652 datasheet, 74HC173N,652 pinout, 74HC173N,652 application, or 74HC173N,652 equivalent, key selection criteria include asynchronous master reset behavior, gated clock-enable logic, 3-state output timing (tPZH/tPHZ), and compatibility with 74LSTTL-level systems.

Technical Context

The 74HC173N,652 implements four independent edge-triggered D flip-flops sharing common clock (CP), master reset (MR), and dual enable inputs (E1/E2). Its register load operation requires both E1 and E2 LOW at the rising edge of CP; otherwise, data is held. MR is asynchronous and active-HIGH, forcing all Qn outputs to LOW regardless of clock or enable state.

Output buffering uses a 2-input NOR gate controlling 3-state drivers - both OE1 and OE2 must be LOW for Q0–Q3 to drive bus lines; any OE HIGH places outputs in high-impedance Z-state. This separation ensures output control is fully decoupled from register state transitions.

Key Specifications

Pinout & Package

74HC173N,652 is supplied in a 16-pin plastic dual in-line package (DIP) with 0.3-inch body width and through-hole mounting.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 4-bit D-type register applications.

Compared with 74HC173N,652, the 74HCT173N,652 offers improved input compatibility with older TTL families but identical timing and output behavior, while SN74HC173N provides equivalent functionality with minor parametric variance and alternate supply-chain traceability.

Availability

74HC173N,652 is available at Aetrix Electronics and suitable for industrial control systems, test instrumentation, and legacy hardware restoration requiring stable component supply and long-term obsolescence management.

Supply support for 74HC173N,652 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

Nexperia is a global leader in high-volume discrete, logic, and power MOSFET semiconductors, formed in 2017 from the former NXP Standard Products division.

The 74HC173N,652 belongs to Nexperia's 74HC/HCT logic family - engineered for robustness, low power, and seamless interoperability in industrial, automotive, and computing applications where reliability and pin compatibility are essential.

FAQ

What is the operating voltage range for the 74HC173N,652?

The 74HC173N,652 operates across a supply voltage range of 2.0 V to 6.0 V. This wide range supports both low-power portable devices and standard 5 V logic systems. At VCC = 2.0 V, it maintains guaranteed functionality with reduced speed; at VCC = 6.0 V, it meets full AC specifications including 88 MHz maximum clock frequency and 17 ns typical propagation delay - all verified per JEDEC standard no. 7A.

How does the master reset (MR) function in the 74HC173N,652?

The MR input in the 74HC173N,652 is an asynchronous active-HIGH signal that forces Q0–Q3 to LOW immediately, independent of clock or enable states. Its 17 ns typical propagation delay (MR→Q) and 20 ns minimum pulse width (at VCC = 4.5 V) ensure deterministic clearing even during transient conditions. Unlike synchronous reset variants, MR overrides all register operations - making the 74HC173N,652 suitable for fail-safe initialization in safety-critical logic paths.

Can the 74HC173N,652 replace a 74LS173 in existing designs?

Yes, the 74HC173N,652 is pin-compatible and electrically compatible with the 74LS173 for most applications. It matches the same 16-pin DIP footprint and provides equivalent logic functionality, including positive-edge triggering, 3-state outputs, and master reset. While its CMOS inputs draw negligible current versus TTL, designers should verify that driving sources meet HC input voltage thresholds (VIH ≥ 3.5 V at VCC = 5 V) - unlike LS, which accepts 2.0 V as VIH.

What is the purpose of the dual enable inputs (E1 and E2) in the 74HC173N,652?

The dual enable inputs E1 and E2 in the 74HC173N,652 provide redundant gating for the parallel load function: both must be LOW to capture D0–D3 on the next CP rising edge. If either E1 or E2 is HIGH before the clock edge, the register holds its prior state. This design allows flexible control - for example, one enable can be tied to a system-wide strobe while the other serves as a local channel select - enhancing configurability without external logic.

Does the 74HC173N,652 support hot-swapping or bus-sharing applications?

Yes, the 74HC173N,652 supports bus-sharing via its independent 3-state output control: OE1 and OE2 must both be LOW to drive Q0–Q3; either HIGH places outputs in high-impedance Z-state. This allows multiple 74HC173N,652 devices to share a common data bus without contention. However, hot-swapping requires external protection circuitry - the device itself does not include live-insertion safeguards or power sequencing logic.