NXP Semiconductors 74HCT6323AD,112

Overview

74HCT6323AD,112 from Nexperia is a programmable 3-stage ripple counter with integrated crystal oscillator and 3-state output buffer, designed for third-overtone crystal operation up to 50 MHz at VCC = 5 V ± 10%. It features asynchronous master reset (MR), dual mode-select inputs (S1/S2) for divide-by-1/2/4/8, on-chip 7 pF capacitors per oscillator pin, and TTL-compatible input thresholds. Used in compact timing modules requiring stable frequency division without external load capacitors.

For engineers reviewing the 74HCT6323AD,112 datasheet, 74HCT6323AD,112 pinout, 74HCT6323AD,112 application, or 74HCT6323AD,112 equivalent, this device serves as a self-contained CIO (Compact Integrated Oscillator) solution where precise clock division, low external component count, and wide temperature operation (–40 °C to +125 °C) are critical.

Technical Context

The device integrates a Pierce-type oscillator configurable for fundamental or third-overtone crystal modes, with internal 7 pF capacitors enabling third-overtone operation up to 50 MHz without external load caps. Its 3-stage binary ripple counter advances on the negative-going edge of X1 and supports four fixed division ratios via S1/S2 logic levels.

MR provides asynchronous reset: a LOW halts oscillation, clears the counter, and places OUT in high-impedance state. Inputs MR, S1, and S2 include internal pull-up resistors (~25 µA at VCC = 5.5 V), allowing floating operation while ensuring defined inactive states.

Key Specifications

Pinout & Package

Package: SO8 (SOT96-1), plastic small outline, 8 leads, body width 3.9 mm, lead pitch 1.27 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable oscillator-counter applications.

Compared with 74HC6323AD,112 and CD74HC4060M96, the 74HCT6323AD,112 uniquely combines TTL-compatible inputs, on-chip load capacitance, and selectable division in a single SO8 package-enabling compact, robust CIO implementations without design compromises.

Availability

74HCT6323AD,112 is available at Aetrix Electronics and suitable for industrial timer modules, automotive engine control units, medical infusion pumps, and industrial PLC real-time clocks requiring stable component supply across extended temperature ranges.

Supply support for 74HCT6323AD,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 delivering high-performance, reliable logic, analog, and MOSFET solutions with focus on efficiency, miniaturization, and automotive-grade quality.

The 74HCT6323A series belongs to Nexperia's high-reliability logic portfolio, engineered specifically for timing-critical embedded systems where integration, temperature resilience, and ease of crystal implementation are primary design goals.

FAQ

Can 74HCT6323AD,112 operate with a fundamental-mode crystal?

Yes. The device supports both fundamental and third-overtone crystal modes. For fundamental operation (1–25 MHz), use external load capacitors (e.g., 22–37 pF) and bias resistor (100 kΩ to 1 MΩ) per Figure 9. Internal 7 pF caps remain active but are insufficient alone for fundamental tuning.

What happens if S1 and S2 pins are left unconnected?

S1 and S2 have internal pull-up resistors (~25 µA at VCC = 5.5 V), so floating pins default to HIGH. This configures the counter for divide-by-8 mode. No external pull-ups are required unless a different default ratio is needed.

Is an external clock allowed at X1, and what are the requirements?

Yes. An external clock may drive X1 directly. X2 must be left floating. Input must meet 74HCT thresholds (VIH ≥ 2.0 V, VIL ≤ 0.8 V), have rise/fall times ≤ 6 ns, and stay within GND–VCC. Counter advances on X1's negative edge.

How does MR interact with oscillator startup and power sequencing?

MR is asynchronous and overrides all functions: LOW forces immediate oscillator stop, counter reset, and OUT high-impedance. Its internal pull-up ensures MR = HIGH at power-on, enabling automatic oscillator startup. No external RC reset circuit is needed.