NXP Semiconductors 74AHC164BQ,115

Overview

74AHC164BQ,115 from Nexperia is an 8-bit serial-in/parallel-out CMOS shift register with dual serial data inputs (DSA, DSB), eight parallel outputs (Q0–Q7), master reset (MR), and edge-triggered clock (CP). It operates from 2.0 V to 5.5 V, supports -40 °C to +125 °C ambient range, and features overvoltage-tolerant inputs up to 5.5 V. Used in LED display drivers, I/O expansion, and serial-to-parallel data conversion in industrial control systems.

For engineers reviewing the 74AHC164BQ,115 datasheet, 74AHC164BQ,115 pinout, 74AHC164BQ,115 application, or 74AHC164BQ,115 equivalent, key selection considerations include its dual-input data enable logic, LOW-to-HIGH clock triggering, active-low synchronous reset, DHVQFN14 thermal-enhanced package, and compatibility with mixed-voltage signal translation.

Technical Context

The device implements an 8-stage positive-edge-triggered shift register with asynchronous active-low master reset. Data enters via either DSA or DSB, with the other input acting as a HIGH-enable gate-enabling flexible serial data routing without external logic. All inputs include Schmitt-trigger action for noise immunity.

It uses standard CMOS level inputs (74AHC variant), delivers rail-to-rail output swing, and maintains balanced propagation delays across all Q outputs. The internal structure comprises eight cascaded D flip-flops with common clock and reset, supporting deterministic timing under varying load capacitance (15 pF to 50 pF) and supply voltage (3.0 V to 5.5 V).

Key Specifications

Pinout & Package

DHVQFN14 (SOT762-1) package: 2.5 mm × 3.0 mm × 0.85 mm body, 14-terminal no-lead quad flat design with exposed thermal pad (non-soldered by default); optimized for thermal performance and PCB space efficiency in high-density layouts.

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 74AHCT164BQ,115, the 74AHC164BQ,115 offers superior noise immunity and wider V_CC flexibility below 4.5 V; versus SN74LV164APW, it trades lower quiescent current for essential overvoltage protection in heterogeneous voltage systems.

Availability

74AHC164BQ,115 is available at Aetrix Electronics and suitable for LED display drivers, microcontroller I/O expansion, industrial serial bus interfaces, and legacy protocol translators requiring stable component supply across extended temperature ranges.

Supply support for 74AHC164BQ,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 emphasis on efficiency, miniaturization, and automotive-grade reliability.

The 74AHC164BQ,115 belongs to Nexperia's advanced AHC logic family, designed specifically for low-power, high-noise-immunity serial-to-parallel data conversion in space-constrained industrial and consumer applications.

FAQ

What is the maximum clock frequency supported by the 74AHC164BQ,115?

The 74AHC164BQ,115 supports up to 115 MHz maximum clock frequency at V_CC = 4.5–5.5 V with 15 pF load, and 85 MHz at 50 pF load. At 3.0–3.6 V, max frequency drops to 65 MHz (15 pF) and 35 MHz (50 pF). These values assume proper decoupling, controlled impedance traces, and adherence to setup/hold timing requirements.

Can DSA and DSB be used simultaneously for data input?

No - DSA and DSB are logically OR'd internally with enable gating: only one input is active at a time. When DSB = HIGH, DSA serves as the data input; when DSA = HIGH, DSB serves as the data input. Simultaneous LOW on both disables data entry. This architecture prevents bus contention and eliminates need for external multiplexing logic.

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

No - the exposed thermal pad (pin 1 index area) has no electrical function and may remain unsoldered. If soldered, it must be left electrically floating or connected to GND; it must not be tied to V_CC or any other voltage. Soldering improves thermal resistance by ~15 °C/W but is optional per Nexperia's mechanical recommendations.

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

MR is asynchronous and active-LOW: asserting MR immediately forces all Q0–Q7 outputs LOW, overriding CP and data inputs. Release of MR does not trigger a clock event - the register remains in cleared state until the next rising CP edge, at which point normal shifting resumes from zero state. MR requires minimum 5 ns pulse width for reliable assertion.