Renesas HD4074889H

Overview

HD4074889H from Renesas Electronics is a 4-bit single-chip microcontroller with on-chip ZTAT™ PROM (16,384 words), 1,344-digit RAM, integrated LCD controller/driver (32 segments × 4 commons), 6-channel 8-bit A/D converter, and 46 I/O pins-including 4 large-current source (10 mA max) and 8 sink (15 mA max) pins. It operates from 1.8 V to 5.5 V and targets low-power display panel control in pagers and remote controllers.

For engineers reviewing the HD4074889H datasheet, HD4074889H pinout, HD4074889H application, or HD4074889H equivalent, key selection factors include its ZTAT™ PROM architecture for rapid prototyping, sub-32.768 kHz RTC support, four low-power modes (stop/watch/standby/subactive), and 80-pin QFP (FP-80A) package compatibility with legacy HD404889 designs.

Technical Context

The HD4074889H implements a 4-bit CPU core with subroutine stack depth up to 16 levels and supports instruction execution as fast as 0.89 µs at 4.5 MHz. Its on-chip peripherals include two 8-bit timers, one 16-bit timer (configurable as dual 8-bit), an 8-bit input capture circuit, two timer outputs (one PWM-capable), and a clock-synchronous 8-bit serial interface.

It integrates a dedicated LCD driver with programmable bias and internal voltage divider (V0–V3), analog input multiplexing across six pins (R70–R81), and three external interrupt inputs (including edge-programmable INT0/INT1). The sub-oscillator supports 32.768 kHz crystal operation for real-time clock functions without external components.

Key Specifications

Pinout & Package

HD4074889H uses an 80-pin plastic QFP package (FP-80A), identical in footprint and pin assignment to the mask ROM HD404889H variant. Pin functions are validated per Renesas Rev.6.00 datasheet (pages 10–11, 19).

Key Features

Applications

Equivalent & Alternatives

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

Compared with HD404889H, HD4074889H trades mask ROM inflexibility for rapid firmware iteration, while HD4074899H extends analog capability at identical package and toolchain compatibility-making HD4074889H the balanced choice for display-centric, cost-constrained, and development-phase designs.

Availability

HD4074889H is available at Aetrix Electronics and suitable for pager display control, remote controller interface, and home appliance keypad panel applications requiring stable component supply and long-lifecycle support.

Supply support for HD4074889H 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

Renesas Electronics Corporation is a global semiconductor leader specializing in microcontrollers, analog, power, and SoC solutions for automotive, industrial, and consumer markets.

The HD4074889H belongs to the HD404889/HD404899 Series of low-voltage 4-bit AS microcomputers designed specifically for cost-sensitive, battery-operated display and control systems with integrated LCD and A/D functionality.

FAQ

What is the memory configuration of the HD4074889H?

The HD4074889H contains 16,384-word ZTAT™ PROM (functionally equivalent to 27256 EPROM) and 1,344-digit RAM. This PROM is field-programmable and retains code without external UV erasure-enabling rapid firmware updates during development and early production phases before final mask ROM transition.

Does the HD4074889H support real-time clock functionality?

Yes, the HD4074889H includes a dedicated 32.768 kHz sub-oscillator circuit with X1/X2 pins for connecting a standard watch crystal. This enables autonomous real-time clock operation, calendar functions, and wakeup-from-stop mode using time-based interrupts-without loading the main CPU or consuming system clock resources.

What LCD configurations does the HD4074889H support?

The HD4074889H supports static and multiplexed LCD displays up to 32 segments × 4 commons (128 segments total). Its integrated driver provides programmable bias via V0–V3 pins and internal voltage division, eliminating external resistor networks and enabling software-tuned contrast for varying ambient lighting conditions.

Can the HD4074889H replace the HD404889H in existing designs?

Yes-the HD4074889H shares identical pinout, package (FP-80A), electrical specifications, and peripheral register mapping with the HD404889H. The only functional difference is the ZTAT™ PROM versus mask ROM, making it a drop-in replacement for prototyping and pre-production builds where firmware iteration is required.

What are the maximum drive capabilities of the HD4074889H I/O pins?

The HD4074889H provides 4 large-current source pins (D0–D3, 10 mA max each) and 8 large-current sink pins (D4–D11, 15 mA max each). These are rated for direct LED driving, buzzer excitation, and small-signal relay control-reducing or eliminating the need for external driver transistors in many display and interface applications.