Texas Instruments CD74HC147M96

Overview

CD74HC147M96 from Texas Instruments is a high-speed CMOS 9-input priority encoder performing 10-line-to-4-line active-low encoding with decimal zero implied, operating from 2V to 6V supply, featuring 13ns typical propagation delay at 5V/15pF, -55°C to +125°C temperature range, and buffered inputs/outputs for industrial control panel key encoding.

For engineers reviewing the CD74HC147M96 datasheet, CD74HC147M96 pinout, CD74HC147M96 application, or CD74HC147M96 equivalent, this device serves as a drop-in replacement for legacy LSTTL encoders in space-constrained SOIC-16 designs requiring low-power, wide-voltage, and high-noise-immunity logic encoding with deterministic priority resolution.

Technical Context

The CD74HC147M96 implements combinational priority encoding logic where nine active-low inputs (I0–I9) are mapped to four active-low binary outputs (Y0–Y3), with I9 assigned highest priority; simultaneous active inputs resolve to the numerically highest asserted input, and all-high inputs encode "zero" as all outputs go high.

It uses silicon-gate CMOS technology with rail-to-rail input voltage tolerance (0V to VCC), guaranteed noise immunity of 30% of VCC at 5V, and fanout capability of 15 LSTTL loads - enabling direct interface with legacy TTL systems without level-shifting while maintaining sub-100µA quiescent current across its full temperature range.

Key Specifications

Pinout & Package

CD74HC147M96 is housed in a 16-pin SOIC (D) package measuring 9.90mm × 3.90mm, with standard 1.27mm pitch, gull-wing leads, and RoHS-compliant NiPdAu/Sn lead finish rated MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar priority encoder applications.

Compared with SN74HC147N and CD74HCT147M96, CD74HC147M96 offers broader supply flexibility (2–6V), lower static current, and optimized SOIC-16 tape-and-reel delivery - making it ideal for new SMT designs targeting cost, power, and manufacturability.

Availability

CD74HC147M96 is available at Aetrix Electronics and suitable for industrial HMI panels, automotive switch matrices, test equipment front ends, and legacy system upgrades requiring stable component supply and long-term obsolescence mitigation.

Supply support for CD74HC147M96 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 leader specializing in analog, embedded processing, and logic ICs, with over 90 years of innovation in industrial, automotive, and communications markets.

CD74HC147M96 belongs to TI's HC-series high-speed CMOS logic portfolio, engineered for low-power, wide-voltage, and high-noise-immunity digital interfacing in harsh-environment applications.

FAQ

What is the logic polarity of CD74HC147M96 inputs and outputs?

The CD74HC147M96 features active-low inputs (I0–I9) and active-low outputs (Y0–Y3). All nine inputs must be high to encode "zero", resulting in all four outputs going high. This polarity simplifies direct connection to open-collector or push-pull switch interfaces without inversion logic.

Does CD74HC147M96 support 3.3V operation?

Yes, CD74HC147M96 fully supports 3.3V operation within its 2V–6V supply range. At VCC = 3.3V, it maintains guaranteed noise margins, 10pF input capacitance, and sub-100µA quiescent current - making it suitable for mixed-voltage systems interfacing with 3.3V microcontrollers.

Is CD74HC147M96 pin-compatible with the older 74LS147?

Yes, CD74HC147M96 is pin-compatible with 74LS147 in SOIC-16 footprint, sharing identical pin numbering and function mapping. However, it requires no external pull-ups and draws significantly less current, enabling direct replacement in most LS-based designs with verified timing margins.

What is the purpose of the NC pin (Pin 15) on CD74HC147M96?

Pin 15 on CD74HC147M96 is a no-connect terminal with no internal bond wire or circuit connection. It must remain unconnected and floating - neither grounded nor tied to VCC - to avoid parasitic coupling or package stress effects that could impact timing or ESD robustness.

How does CD74HC147M96 handle simultaneous active inputs?

CD74HC147M96 resolves simultaneous active inputs using fixed hardware priority: I9 (highest) > I8 > I7 > I6 > I5 > I4 > I3 > I2 > I1 > I0 (lowest). When multiple inputs are low, only the highest-priority asserted input determines the output code - ensuring deterministic behavior without software arbitration.