Nexperia USA Inc. 74AHCT164BQ,115

Overview

74AHCT164BQ,115 from Nexperia is an 8-bit serial-in/parallel-out shift register with dual active-HIGH data inputs (DSA and DSB), eight CMOS-compatible parallel outputs (Q0–Q7), edge-triggered clock (CP) on LOW-to-HIGH transitions, and asynchronous master reset (MR). It operates from 4.5 V to 5.5 V, supports -40 °C to +125 °C ambient, and features TTL-level input thresholds for direct interfacing with legacy logic. Used in LED matrix drivers and microcontroller GPIO expansion.

For engineers reviewing the 74AHCT164BQ,115 datasheet, 74AHCT164BQ,115 pinout, 74AHCT164BQ,115 application, or 74AHCT164BQ,115 equivalent, key selection criteria include its dual-input data enable architecture, 11.5 ns max propagation delay at 5 V/50 pF, DHVQFN14 thermal-enhanced package, and guaranteed operation across industrial and extended temperature ranges.

Technical Context

This device implements a synchronous 8-stage shift register with asynchronous active-LOW master reset. Data entry is controlled by mutual enable logic between DSA and DSB: one input acts as data path while the other serves as active-HIGH gate enable. The register updates on each rising edge of CP, with no internal latching beyond the shift register stages.

All inputs tolerate up to 5.5 V regardless of VCC, enabling mixed-voltage translation (e.g., 3.3 V controller driving 5 V peripherals). Input Schmitt triggers provide noise immunity, and output drive strength is specified at ±8 mA at VCC = 4.5 V, supporting direct LED segment control without external buffers.

Key Specifications

Pinout & Package

DHVQFN14 (SOT762-1) package: 2.5 × 3.0 × 0.85 mm body, 14-terminal quad flat no-lead with exposed thermal pad (non-soldered or floating per datasheet guidance).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit serial-in/parallel-out shift register applications.

Compared with 74AHC164BQ,115 and SN74HC164PWR, the 74AHCT164BQ,115 offers superior TTL compatibility for legacy integration and overvoltage-safe inputs for mixed-voltage robustness - making it optimal for industrial upgrades and space-constrained 5 V systems requiring reliability across temperature extremes.

Availability

74AHCT164BQ,115 is available at Aetrix Electronics and suitable for LED display drivers, microcontroller GPIO expansion, industrial serial bus interfaces, and legacy system logic bridges requiring stable component supply across extended temperature and mixed-voltage conditions.

Supply support for 74AHCT164BQ,115 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 robustness for industrial and automotive markets.

The 74AHCT series targets TTL-compatible logic interfacing in industrial control and embedded systems, emphasizing noise immunity, wide operating margins, and thermal resilience in compact packages like DHVQFN.

FAQ

What is the maximum clock frequency supported by the 74AHCT164BQ,115?

The device supports up to 85 MHz maximum frequency at VCC = 5 V and CL = 50 pF, as specified in Table 7 of the datasheet. This assumes clean clock edges with ≤5 ns pulse width and proper PCB layout minimizing trace inductance and capacitive loading. Real-world operation at 65–75 MHz is typical in well-decoupled 5 V systems with controlled-impedance routing.

Can DSA and DSB be used simultaneously for differential data input?

No - DSA and DSB are not differential inputs. They implement OR-gated logic: data enters through whichever input is HIGH while the other is held HIGH to enable. Simultaneous assertion of both does not yield differential behavior; instead, it creates ambiguous enable state and violates the function table's "h l" and "l h" setup requirements. Use only one as data, the other as enable.

Is the exposed thermal pad on the DHVQFN14 package required to be soldered to ground?

No - per datasheet section 5.1, the thermal pad (terminal 1 index area) has no electrical or mechanical requirement to be soldered. If soldered, it must remain electrically floating or connected to GND; it is not internally tied to any net. Thermal performance improvement is marginal unless thermally coupled to a large copper pour.

How does the master reset (MR) interact with the clock during active reset?

MR is asynchronous and dominant: when MR is LOW, all outputs (Q0–Q7) force LOW immediately, regardless of CP state or data inputs. No clock edge is needed - the reset occurs within tPHL (max 11.5 ns) after MR falls. Outputs remain LOW until MR returns HIGH and at least one valid CP rising edge occurs with DSA/DSB properly configured.