Texas Instruments CD4515BE

Overview

CD4515BE from Texas Instruments is a 4-bit latched binary-to-decimal decoder/demultiplexer in a 16-pin plastic DIP package, operating from 3 V to 18 V supply, with typical propagation delay of 120 ns at 5 V and 70 ns at 15 V, used for address decoding and signal routing in legacy CMOS logic systems.

For engineers reviewing the CD4515BE datasheet, CD4515BE pinout, CD4515BE application, or CD4515BE equivalent, key selection considerations include its active-high latch enable (LE), active-low outputs (Y0–Y15), asynchronous reset (MR), and compatibility with CD4000-series logic voltage levels and timing.

Technical Context

The CD4515BE implements a 4-bit binary input (A0–A3) decoded into 16 mutually exclusive active-low outputs (Y0–Y15), controlled by a latched enable (LE) and master reset (MR). It uses standard CMOS silicon-gate technology with buffered outputs.

Its internal architecture includes a 4-bit latch followed by a 1-of-16 decoder stage; output states are held stable during input transitions due to the latch, eliminating glitches common in non-latched decoders. MR forces all outputs high regardless of LE or input state.

Key Specifications

Pinout & Package

CD4515BE is supplied in a 16-lead plastic dual-in-line package (PDIP-16), compliant with JEDEC MS-011, with 0.3-inch body width and 0.1-inch lead pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 4-bit latched decoder applications.

Compared with CD4515BE, CD4514BE offers complementary output polarity for high-active loads, while MC14515B provides a drop-in replacement with identical electrical and mechanical behavior - enabling either functional adaptation or seamless sourcing continuity.

Availability

CD4515BE is available at Aetrix Electronics and suitable for industrial control panels, legacy instrumentation displays, and military communication gear requiring stable component supply over extended product lifecycles.

Supply support for CD4515BE 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 founded in 1930, specializing in analog, embedded processing, and logic ICs with broad industrial, automotive, and aerospace qualification.

The CD4515BE belongs to TI's CD4000B series of radiation-tolerant, wide-supply CMOS logic devices, designed for robustness in harsh environments and long-term reliability in mission-critical systems.

FAQ

What is the function of the MR pin on the CD4515BE?

The MR (Master Reset) pin on the CD4515BE is an asynchronous active-high input that forces all 16 decoded outputs (Y0–Y15) to the high state, regardless of latch enable or address inputs. This provides immediate, timing-independent initialization - essential for safe power-up sequencing or fault recovery in systems using CD4515BE. The MR function remains active even when LE is inactive or V_DD is marginal.

Can CD4515BE operate at 3.3 V supply?

Yes, CD4515BE is fully specified to operate at 3 V minimum supply voltage, making it compatible with 3.3 V logic systems. At 3.3 V, propagation delay increases to approximately 220 ns, and output sink current reduces to ~1.8 mA, but all DC and AC parameters remain guaranteed per datasheet. No level-shifting circuitry is needed when interfacing with 3.3 V microcontrollers.

Is CD4515BE pin-compatible with CD4514BE?

Yes, CD4515BE and CD4514BE share identical pinout, package, supply range, timing, and latch behavior - differing only in output polarity (CD4515BE has active-low outputs, CD4514BE has active-high). This allows direct PCB substitution when logic polarity is accounted for in firmware or downstream circuitry, with no layout changes required.

What is the maximum clock frequency supported by CD4515BE for address updates?

CD4515BE does not use a clock signal; address updates occur on the rising edge of the LE (Latch Enable) input. Given its 120 ns propagation delay at 5 V, the minimum LE pulse period is ~250 ns, supporting effective address update rates up to 4 MHz. For reliable operation, maintain LE pulse width ≥ 100 ns and ensure clean edge monotonicity to avoid metastability.

Does CD4515BE require external pull-up resistors on its outputs?

No, CD4515BE outputs are fully buffered CMOS totem-pole structures capable of both sourcing and sinking current - unlike open-drain devices, they do not require external pull-ups. However, when driving LEDs or relays, connect the load between V_DD and the output pin (for active-low operation), leveraging the device's native 4.2 mA sink capability at 15 V.