Renesas UPD78F0455GB-UEU-AT

Overview

UPD78F0455GB-UEU-AT from Renesas Electronics is an 8-bit single-chip microcontroller in the 78K0/LE3 family, integrating an LCD controller/driver, 64 KB on-chip Flash memory, 4 KB RAM, and a 10-bit ADC. It operates at up to 20 MHz with supply voltage range 2.7–5.5 V and targets embedded control applications requiring segment-based display driving and analog sensing - such as industrial panel meters and home appliance user interfaces.

For engineers reviewing the UPD78F0455GB-UEU-AT datasheet, UPD78F0455GB-UEU-AT pinout, UPD78F0455GB-UEU-AT application, or UPD78F0455GB-UEU-AT equivalent, key selection criteria include its 100-pin LQFP package, integrated LCD bias generation, 29-channel 10-bit ADC, and support for low-power operation modes including HALT and STOP.

Technical Context

The UPD78F0455GB-UEU-AT implements the 78K0 CPU core with 16-bit address space and supports instruction set compatibility across the 78K0 series. It features dual clock sources (main high-speed oscillator and sub-clock for RTC), programmable watchdog timer, and on-chip debug interface via dedicated pins.

Its LCD controller supports static to 1/4-duty drive with up to 320 segments (8 commons × 40 segments), configurable bias voltage (1/2, 1/3, or 1/4), and internal charge pump for VLCD generation - eliminating need for external LCD bias ICs in many designs.

Key Specifications

Pinout & Package

UPD78F0455GB-UEU-AT is housed in a 100-pin LQFP (14 mm × 14 mm, 0.5 mm pitch) package with exposed thermal pad. Pin functions are defined per Renesas User's Manual Rev.2.00 (R01UH0180EJ0200), supporting full I/O multiplexing, dedicated LCD segment/common outputs, and hardware debug interface.

Key Features

Applications

Equivalent & Alternatives

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

Compared with R5F100PLGFB#30 and UPD78F0537GA-GAD-AX, the UPD78F0455GB-UEU-AT uniquely balances integrated LCD driving, moderate memory size, and proven industrial qualification - making it optimal for cost-sensitive, display-integrated control systems where memory headroom is sufficient and external LCD components must be avoided.

Availability

UPD78F0455GB-UEU-AT is available at Aetrix Electronics and suitable for industrial panel meters, home appliance UIs, medical diagnostic tools, and building automation sensors requiring stable component supply and long-term production continuity.

Supply support for UPD78F0455GB-UEU-AT 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 manufacturer headquartered in Japan, specializing in microcontrollers, analog, power, and SoC solutions for industrial, automotive, and infrastructure markets.

The 78K0/Lx3 product line was designed specifically for cost-effective, low-power embedded control applications requiring integrated peripherals - especially LCD display driving, analog sensing, and robust real-time operation in harsh environments.

FAQ

What is the maximum operating frequency of the UPD78F0455GB-UEU-AT?

The UPD78F0455GB-UEU-AT supports a maximum main system clock frequency of 20 MHz, delivering up to 20 MIPS performance. This is achieved using the on-chip high-speed oscillator or an external crystal up to 20 MHz. The CPU core maintains timing integrity across the full 2.7–5.5 V supply range, and the UPD78F0455GB-UEU-AT datasheet specifies setup/hold margins validated at this speed under worst-case voltage and temperature conditions.

Does the UPD78F0455GB-UEU-AT include an integrated LCD bias generator?

Yes, the UPD78F0455GB-UEU-AT includes a fully integrated LCD bias generator with internal charge pump. It supports selectable bias ratios (1/2, 1/3, or 1/4) and drives up to 8 commons and 40 segments directly. No external resistive divider or charge-pump IC is required - the UPD78F0455GB-UEU-AT generates VLCD internally and regulates it to maintain stable contrast across temperature and supply variations.

How many analog input channels does the UPD78F0455GB-UEU-AT ADC support?

The UPD78F0455GB-UEU-AT integrates a 10-bit successive-approximation ADC with 29 selectable analog input channels. These include dedicated pins and multiplexed port pins, supporting simultaneous sampling via internal sample-and-hold. The ADC features built-in reference voltage (VREF = AVDD), ±1 LSB integral nonlinearity, and conversion times as fast as 1.2 μs per channel - all confirmed in the UPD78F0455GB-UEU-AT electrical characteristics table.

Is the UPD78F0455GB-UEU-AT pin-compatible with other 78K0/LE3 microcontrollers?

Yes, the UPD78F0455GB-UEU-AT shares the same 100-pin LQFP package and pinout with other 78K0/LE3 devices such as UPD78F0451 through UPD78F0454 and UPD78F0461 through UPD78F0465. Functionally identical pins (e.g., COM0–COM7, SEG0–SEG39, RESET, REGC) retain consistent placement and behavior - enabling hardware reuse across variants within the LE3 group as documented in Renesas User's Manual R01UH0180EJ0200.

What debug interface does the UPD78F0455GB-UEU-AT support?

The UPD78F0455GB-UEU-AT supports Renesas' single-pin on-chip debugging (OCDS) interface via P10, compatible with QB-MINI2 and E8a debug emulators. This interface enables flash programming, breakpoint setting, register inspection, and real-time trace without requiring additional pins or external JTAG circuitry - simplifying board layout and reducing debug connector footprint compared to multi-pin alternatives.