Texas Instruments CD74HC4511E

Overview

CD74HC4511E from Texas Instruments is a BCD-to-7-segment latch/decoder/driver IC in 16-pin PDIP package, operating from 2 V to 6 V. It features input latching, active-low blanking (BL), lamp-test (LT), and latch-enable (LE) control - enabling direct drive of common-cathode 7-segment displays in digital instrumentation and industrial panel meters.

For engineers reviewing the CD74HC4511E datasheet, CD74HC4511E pinout, CD74HC4511E application, or CD74HC4511E equivalent, key selection criteria include its 10 mA sourcing capability at 6 V, latch-enabled BCD storage, lamp-test functionality, and compatibility with HC logic families across extended temperature ranges.

Technical Context

The CD74HC4511E implements a synchronous latch-decoder architecture: when LE is high, D0–D3 inputs are latched; when LE is low, outputs follow inputs transparently. Its output stage uses standard-size CMOS transistors optimized for segment sourcing rather than sinking.

It supports dual-mode operation via BL (blanking all segments) and LT (forcing all segments on for visual verification). Propagation delays are balanced across segments (e.g., 51 ns max tpd at 6 V, CL = 50 pF), and input transition times are specified down to 400 ns at 6 V - ensuring reliable timing in multiplexed display systems.

Key Specifications

Pinout & Package

CD74HC4511E is supplied in a 16-pin plastic dual in-line package (PDIP-N), body size 19.31 mm × 6.35 mm, with 2.54 mm lead pitch and through-hole mounting.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar BCD-to-7-segment latch/decoder/driver applications.

Compared with CD74HCT4511E and SN74LS47N, CD74HC4511E provides broader supply range, integrated latching, and lamp-test capability - making it the optimal choice for new designs requiring low-power, flexible, and self-diagnosing display interfaces.

Availability

CD74HC4511E is available at Aetrix Electronics and suitable for industrial panel meters, digital multimeters, and test equipment front panels requiring stable component supply and long-term obsolescence management.

Supply support for CD74HC4511E 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 solutions with over 50 years of innovation in industrial and automotive electronics.

The CD74HC4511E belongs to TI's HC-series high-speed CMOS logic family, designed specifically for low-power, noise-immune BCD-driven display interfaces in harsh industrial environments.

FAQ

What is the maximum supply voltage for CD74HC4511E?

The CD74HC4511E supports a maximum supply voltage of 6 V, with absolute maximum rating at 7 V. Operation above 6 V violates recommended conditions and risks parametric shift or reliability degradation. For robust long-term use, maintain VCC within 2 V to 6 V per the datasheet's recommended operating conditions.

Can CD74HC4511E drive common-anode displays?

No, CD74HC4511E is designed exclusively for common-cathode 7-segment displays: its a–g outputs are active-high sourcing drivers. To interface with common-anode displays, an external inverting buffer or NPN transistor array is required - which adds complexity and power loss not present in the native common-cathode configuration supported by CD74HC4511E.

How does the latch-enable (LE) pin affect CD74HC4511E behavior?

When LE is high, CD74HC4511E latches the current D0–D3 BCD input; outputs remain stable regardless of subsequent input changes. When LE is low, outputs track D0–D3 inputs transparently. This dual-mode operation allows CD74HC4511E to hold display digits steady during bus contention or asynchronous updates - a key advantage over non-latching decoders like SN74LS47.

What is the purpose of the BI/RBO pin on CD74HC4511E?

The BI/RBO pin serves two functions: as active-low Blanking Input (BI) to disable all segment outputs, and as Ripple Blanking Output (RBO) - an open-collector signal that goes low when the displayed digit is zero. In multi-digit displays, RBO from a less-significant digit can blank the more-significant digit, enabling leading-zero suppression without MCU intervention - a feature directly supported by CD74HC4511E's internal logic.

Does CD74HC4511E require external pull-up resistors on its outputs?

No, CD74HC4511E does not require external pull-up resistors: its a–g outputs are CMOS totem-pole drivers capable of sourcing up to 10 mA at 6 V. Pull-ups would conflict with the active-high sourcing architecture and degrade performance. External current-limiting resistors (typically 220 Ω–1 kΩ) are required in series with each segment LED to set forward current - but these are not pull-ups and serve a different electrical function.