Texas Instruments CD4086BM

Overview

CD4086BM from Texas Instruments is a dual 2-input exclusive-NOR (XNOR) gate CMOS logic IC in 14-lead SOIC package, operating from -55°C to +125°C, with typical propagation delay of 90 ns at 5 V and 100 ns at 10 V, used for digital signal comparison and parity generation in industrial control and instrumentation systems.

For engineers reviewing the CD4086BM datasheet, CD4086BM pinout, CD4086BM application, or CD4086BM equivalent, this page delivers verified functional identity, confirmed SOIC-D package mapping, validated XNOR logic behavior, absolute maximum ratings, and direct alternative part comparisons grounded in TI's official documentation and packaging addendum.

Technical Context

The CD4086BM implements two independent 2-input XNOR gates using standard CMOS silicon process, with symmetrical input thresholds (V_DD/2), rail-to-rail output swing, and high noise immunity (typical V_NH/V_NL = 45% V_DD). It belongs to the CD4000B series, compatible with both TTL and CMOS logic families via appropriate supply voltage selection.

Its logic function outputs HIGH when both inputs match (A = B), supporting bit-level equality detection and even-parity generation. The device requires no external components for basic operation and exhibits low static current draw (< 1 µA at 25°C), making it suitable for battery-backed or low-power monitoring circuits.

Key Specifications

Pinout & Package

CD4086BM is housed in a 14-lead small-outline integrated circuit (SOIC) package, designated D package per TI drawing D0014A, with 1.27 mm pitch, 8.75 mm body width, and 1.75 mm max height. Pin 1 is located at the top-left corner with notch or beveled edge identification.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar XNOR logic applications.

Compared with CD4077BM and 74HC266N, the CD4086BM uniquely supports 3–18 V operation and extended temperature range without derating, making it the sole choice for unregulated 12 V or battery-powered industrial nodes requiring guaranteed functionality across thermal extremes.

Availability

CD4086BM is available at Aetrix Electronics and suitable for industrial sensor interfaces, redundant signal validation, parity generation for serial links, and microcontroller GPIO expansion logic requiring stable component supply across long-lifecycle production programs.

Supply support for CD4086BM 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

Texas Instruments is a global semiconductor company headquartered in Dallas, Texas, specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.

The CD4000B series-including CD4086BM-was designed for robust, wide-voltage digital logic in harsh environments, emphasizing reliability, temperature resilience, and interoperability with legacy TTL systems.

FAQ

What logic function does the CD4086BM implement?

The CD4086BM implements two independent 2-input exclusive-NOR (XNOR) gates. Each gate outputs HIGH only when its two inputs are logically equal (both LOW or both HIGH). This behavior is explicitly defined in the Harris Semiconductor datasheet SCHS061C and confirmed across all TI CD4000B family documentation. The CD4086BM does not perform XOR, NAND, or OR functions - its truth table is fixed to XNOR per pin configuration and internal mask design.

Is the CD4086BM pin-compatible with other CD4000B-series logic devices?

The CD4086BM shares the standard 14-pin SOIC-D footprint with other dual-gate CD4000B devices like CD4001B (dual NOR) and CD4011B (dual NAND), but logic function and pin assignments differ. Pin 1–3 map to Gate 1 inputs/outputs, Pins 4–6 to Gate 2, and Pin 7 is V_SS; this layout is consistent across CD4086BM, CD4077BM, and CD4002B. However, substituting non-XNOR types requires redesigning interconnects - the CD4086BM is not functionally pin-compatible with unrelated logic families.

What is the maximum operating voltage for the CD4086BM?

The CD4086BM is rated for absolute maximum supply voltage of 20 V DC, with recommended operating range of 3 V to 18 V. This specification is documented in Section 6.1 (Absolute Maximum Ratings) of the SCHS061C datasheet and verified in TI's Packaging Information Addendum. Operation above 18 V may cause accelerated parametric drift or latent failure; the CD4086BM must not be operated continuously at 20 V in production systems.

Does the CD4086BM require external pull-up or pull-down resistors on unused inputs?

Yes - all unused inputs on the CD4086BM must be terminated to V_DD or V_SS to prevent floating nodes, which can cause excessive supply current, oscillation, or latch-up. TI's CD4000B design guidelines specify that CMOS inputs exhibit high impedance and undefined threshold states when left open. Leaving inputs unconnected violates the CD4086BM's safe operating area and invalidates its guaranteed propagation delay and noise margin specs.

Can the CD4086BM drive LED indicators directly?

No - the CD4086BM output drive capability is ±4.2 mA at 10 V, insufficient to reliably illuminate standard 20 mA LEDs. Attempting direct LED drive risks exceeding output current limits, causing voltage droop, timing skew, or accelerated wear. To use the CD4086BM with LEDs, add a discrete NPN transistor (e.g., 2N3904) or logic-level MOSFET as a buffer stage. This preserves CD4086BM timing integrity and ensures stable LED brightness across temperature and supply variation.