NXP Semiconductors MC14489BPE

Overview

MC14489BPE from Motorola is a CMOS multi-character LED display and lamp driver with integrated 7-segment decoder, 24-bit display register, and 8-bit configuration register. It drives up to 5-digit common-cathode displays (or 25 discrete lamps) via multiplexed-by-5 anode current sources (a–h) and bank FET switches (Banks 1–5), operating at 4.5–5.5 V with single-resistor brightness control. Used in industrial panel meters and instrumentation displays.

For engineers reviewing the MC14489BPE datasheet, MC14489BPE pinout, MC14489BPE application, or MC14489BPE equivalent, key selection factors include its SPI/MICROWIRE-compatible serial interface, BitGrabber™ random-access register architecture, 1 kHz refresh rate, ±15 µA input leakage, and -40°C to +130°C junction temperature rating.

Technical Context

The MC14489BPE implements a 24½-stage static shift register with Schmitt-triggered Data In/Clock/Enable inputs, enabling DC-to-4 MHz clock operation. Its on-chip decoder supports triple-mode output: No Decode (lamp control), Hex Decode (0–F), and Special Decode (15 letters/symbols), configurable per bank via C1–C7 bits.

It uses a patented BitGrabber™ register system eliminating address/steering bits - 8-bit transfers update the configuration register, 24-bit transfers update the display register. The chip integrates power-on reset (POR), low-power mode (blanks display, reduces IDD to 100 µA), and EMI-minimizing bank-switching circuitry with 20% duty cycle.

Key Specifications

Pinout & Package

MC14489BPE is housed in a 20-pin plastic DIP (Dual In-line Package), Case 73B, with 0.3-inch body width and standard through-hole mounting.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED display driver applications.

Compared with MAX6954 and TM1637, the MC14489BPE uniquely combines SPI/MICROWIRE compatibility, per-bank decode configurability, 320 mA bank sinks, and -40°C to +130°C operation - making it the only option supporting ruggedized 5-digit + lamp applications with minimal external components.

Availability

MC14489BPE is available at Aetrix Electronics and suitable for industrial panel meters, automotive instrument clusters, test equipment, and medical device displays requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for MC14489BPE 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

Motorola Semiconductor (now part of NXP Semiconductors) pioneered high-reliability analog and mixed-signal ICs for industrial and automotive markets.

The MC14489BPE belongs to Motorola's legacy LED display driver family, engineered specifically for robust, low-component-count solutions in harsh-environment instrumentation where serial bus efficiency and thermal resilience are critical.

FAQ

What is the maximum number of digits the MC14489BPE can drive in a single-device configuration?

The MC14489BPE can drive up to 5 digits plus decimals in a single-device configuration - implemented as five 7-segment banks (a–g) plus decimal point (h) per bank. Figure 9 confirms this 5-character common-cathode layout. It also supports 4½-digit displays (e.g., overflow "1" on h) and 25 discrete lamps, as detailed in the Applications Information section.

Does the MC14489BPE require external current-limiting resistors for each LED segment?

No, the MC14489BPE does not require per-segment current-limiting resistors. It integrates matched anode current sources (a–h) controlled by a single external resistor (Rx) connected between Pin 8 and VSS. This architecture eliminates 35+ discrete resistors in a 5-digit display, reducing BOM cost and PCB area while ensuring uniform brightness.

How does the MC14489BPE handle electromagnetic interference (EMI) during display multiplexing?

The MC14489BPE incorporates on-chip EMI suppression techniques including controlled bank-switching timing, minimized current slew rates, and optimized power rail routing. These features reduce spiking on VDD/VSS and radiated emissions - especially critical in precision analog systems. In low-power mode, EMI is eliminated entirely as the oscillator and mux circuitry are disabled.

Can the MC14489BPE be cascaded with other devices, and if so, how many?

Yes, the MC14489BPE supports daisy-chain cascading via its Data Out (Pin 18) to Data In (Pin 12) interface. Figures 10–14 document configurations for 2 to 6 devices. Table 2 specifies byte-length rules: for N cascaded devices, display register updates require 3N bytes (with 0–2 leading "don't care" bytes), enabling scalable digit counts up to 30+ digits.

What is the function of the D23 bit in the MC14489BPE display register?

The D23 bit in the MC14489BPE display register controls coarse brightness: when high, it enables full peak anode current (e.g., ~20 mA with Rx = 2 kΩ); when low, it reduces current by ~50%. This digital dimming feature allows dynamic brightness adjustment over serial interface without changing Rx - essential for adapting to ambient light or extending LED life.