Nexperia USA Inc. 74HC151BQX

Overview

74HC151BQX from Nexperia is an 8-input CMOS multiplexer with complementary outputs (Y and Y), three binary select inputs (S0–S2), and active-low enable (E). It routes one of eight data inputs (I0–I7) to Y/Y based on select logic, operates from 2.0 V to 6.0 V, supports -40 °C to +125 °C, and features clamp diodes for overvoltage-tolerant interfacing in digital control and signal routing applications.

For engineers reviewing the 74HC151BQX datasheet, 74HC151BQX pinout, 74HC151BQX application, or 74HC151BQX equivalent, this device serves as a low-power, TTL-compatible (via 74HCT variant) data selector in microcontroller I/O expansion, test equipment signal switching, and industrial logic sequencing where deterministic 8:1 routing with dual-phase output is required.

Technical Context

The 74HC151BQX implements standard Boolean multiplexer logic: when E = LOW, Y = I_n and Y = I̅_n, where n = S2S1S0₂; when E = HIGH, Y = LOW and Y = HIGH regardless of selects. Its CMOS architecture ensures rail-to-rail output swing, high noise immunity (>50% VCC), and static input protection via integrated clamp diodes.

It operates across two logic families: 74HC151BQX accepts CMOS-level inputs (VIH ≥ 70% VCC), while the pin-compatible 74HCT151BQX variant accepts TTL-level inputs (VIH ≥ 2.0 V at VCC = 4.5–5.5 V). Both share identical pinout, timing behavior, and DHVQFN16 (SOT763-1) thermal-enhanced package.

Key Specifications

Pinout & Package

DHVQFN16 (SOT763-1) package: 2.5 mm × 3.5 mm × 0.85 mm body, 16-terminal no-lead quad flat design with exposed thermal pad (non-soldered by default); optimized for high-density PCB layouts and improved thermal performance over SO16/TSSOP variants.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-input multiplexer applications.

Compared with 74HCT151BQX and SN74LV151APWR, the 74HC151BQX delivers optimal balance of wide voltage support, industrial temperature rating, and built-in overvoltage protection-making it the default choice for ruggedized embedded control where reliability trumps marginal speed gains.

Availability

74HC151BQX is available at Aetrix Electronics and suitable for industrial sensor hubs, microcontroller I/O expansion, automotive diagnostic interfaces, and test equipment signal routing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 74HC151BQX 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 focused on essential efficiency technologies, delivering high-performance logic, analog, and MOSFET solutions for automotive, industrial, and consumer markets.

The 74HC151BQX belongs to Nexperia's 74HC logic family-designed specifically for low-power, high-noise-immunity digital signal routing in space-constrained, thermally demanding applications where pin compatibility and long-term supply stability are critical.

FAQ

What is the maximum clock frequency supported by the 74HC151BQX for reliable data selection?

The 74HC151BQX does not operate on a clock; it is asynchronous. Its maximum usable data rate is determined by propagation delay: at VCC = 6.0 V and CL = 50 pF, tpd(In→Y) is 43 ns max, supporting input signal transitions up to ~12 MHz for guaranteed setup/hold compliance in static selection scenarios. For dynamic addressing, ensure S0–S2 settle ≥43 ns before sampling Y.

Can the 74HC151BQX be used with 3.3 V microcontrollers without level shifting?

Yes. With VCC = 3.3 V, the 74HC151BQX accepts CMOS-level inputs (VIH ≥ 2.31 V, VIL ≤ 1.65 V), matching standard 3.3 V logic thresholds. Its outputs swing rail-to-rail (VOH ≥ 3.15 V, VOL ≤ 0.15 V at IO = ±4 mA), ensuring clean interfacing with 3.3 V MCU GPIOs without external translators.

Is the exposed thermal pad on the DHVQFN16 package required to be soldered to ground?

No. Per Nexperia's datasheet (SOT763-1), terminal 1's thermal pad has no electrical or mechanical requirement to be soldered. If connected, it must remain floating or be tied to GND - never left unconnected and floating, as that may cause EMI or thermal instability. Most designs connect it to GND for improved heat dissipation and noise rejection.

How does the enable (E) pin affect output states when asserted?

When E is HIGH (active-LOW enable), the 74HC151BQX forces Y = LOW and Y = HIGH regardless of S0–S2 or I0–I7 states. This overrides all data selection, providing a hardware-gated disable function useful for bus contention avoidance, power sequencing, or fault-safe shutdown in safety-critical subsystems.