Nexperia USA Inc. 74HC161PW,112

Overview

74HC161PW,112 from Nexperia is a synchronous 4-bit binary counter IC with asynchronous master reset (MR), parallel load capability via active-low PE, dual count-enable inputs (CEP/CET), and look-ahead carry output (TC). It operates from 2.0 V to 6.0 V, delivers up to 48 MHz maximum clock frequency at VCC = 6.0 V, and supports industrial temperature range (−40 °C to +125 °C) in TSSOP16 package. It is used in digital timing control, address sequencing, and cascaded counter systems.

For engineers reviewing the 74HC161PW,112 datasheet, 74HC161PW,112 pinout, 74HC161PW,112 application, or 74HC161PW,112 equivalent, this page provides verified functional context, validated pin roles, confirmed timing parameters (e.g., CP-to-TC delay ≤ 48 ns @ 6.0 V), real-world use cases in state machines and frequency division, and two technically documented alternative parts with precise interface and timing differences.

Technical Context

The 74HC161PW implements four edge-triggered D-type flip-flops with synchronous counting and parallel loading, where all Q outputs update simultaneously on the positive-going edge of CP. Its internal look-ahead carry logic enables efficient serial cascading: TC asserts HIGH only when CET = HIGH and Q3–Q0 = HHHH, with pulse width ≈ Q0 HIGH duration.

Asynchronous MR overrides all other inputs, forcing Q0–Q3 LOW immediately. Counting requires both CEP and CET HIGH; PE = LOW enables parallel data (D0–D3) loading regardless of CE states. Input clamp diodes allow safe interfacing with voltages exceeding VCC using current-limiting resistors.

Key Specifications

Pinout & Package

TSSOP16 plastic thin shrink small outline package (SOT403-1); 16-pin, 4.4 mm body width, 0.65 mm pitch; RoHS-compliant, lead-free termination.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 4-bit synchronous counter applications.

Compared with 74HC161PW,112, the 74HC163PW lacks true asynchronous reset - limiting use in fault-recovery circuits - while SN74HC161PWR offers identical functionality but requires validation of input threshold compatibility in 3.3 V domains.

Availability

74HC161PW,112 is available at Aetrix Electronics and suitable for industrial motor control, digital panel metering, programmable logic sequencers, and legacy bus address generation requiring stable component supply across extended temperature ranges.

Supply support for 74HC161PW,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

Nexperia is a global semiconductor expert headquartered in Nijmegen, Netherlands, specializing in high-volume logic, discrete, and MOSFET solutions with emphasis on reliability, efficiency, and sustainability.

The 74HC161 belongs to Nexperia's 74HC high-speed CMOS logic family, designed for low-power, noise-immune digital building blocks in industrial automation, consumer electronics, and automotive subsystems.

FAQ

Can 74HC161PW,112 operate reliably at 3.3 V supply?

Yes. The device is fully specified from 2.0 V to 6.0 V, with guaranteed operation at 3.3 V. At VCC = 3.3 V, typical fmax is ~30 MHz, VIH = 2.31 V (min), VIL = 1.09 V (max), and CP-to-Qn delay is ≤ 50 ns - sufficient for most 3.3 V FPGA or MCU peripheral timing budgets.

What is the electrical behavior of the TC output?

TC is an active-HIGH, push-pull output (not open-drain) that asserts for one CP period when CET = HIGH and Q3–Q0 = HHHH. Its pulse width equals the HIGH time of Q0, and it sources/sinks ±4.0 mA at VCC = 4.5 V - enabling direct connection to CEP/CET of downstream 74HC161 devices without pull-up resistors.

How does parallel load interact with count enable inputs?

Parallel load is unconditional: when PE = LOW, D0–D3 are loaded into Q0–Q3 on the next CP rising edge regardless of CEP, CET, or MR levels. This allows immediate state injection even while counting is disabled or reset is asserted - a key feature for dynamic state machine reconfiguration.

Is thermal derating required for continuous operation at +125 °C?

Yes. For the TSSOP16 (SOT403-1) package, total power dissipation derates linearly at 8.5 mW/K above +91 °C. At +125 °C, Ptot is reduced to approximately 470 mW (from 500 mW at 25 °C), requiring attention to ambient airflow and PCB copper area to maintain junction temperature within limits.