Renesas UPD78F0394GC-8EA-A

Overview

UPD78F0394GC-8EA-A from Renesas Electronics is an 8-bit single-chip microcontroller in the 78K0/LE2 family, featuring 32 KB Flash memory, 1 KB RAM, 10-bit A/D converter (5 channels), LCD controller/driver (20 segment × 4 common), and integrated UART0, UART6 (LIN-capable), and I²C interfaces. It operates across 1.8 V to 5.5 V and supports multiple clock sources including internal 8 MHz and 240 kHz ring oscillators, external crystal up to 20 MHz, and 32.768 kHz subclock - used in industrial control panels with integrated display and serial diagnostics.

For engineers reviewing the UPD78F0394GC-8EA-A datasheet, UPD78F0394GC-8EA-A pinout, UPD78F0394GC-8EA-A application, or UPD78F0394GC-8EA-A equivalent, key selection criteria include its 64-pin QFP package, Flash self-programming capability, low-voltage detector (LVI), on-chip debug support, and LIN-compliant UART6 for automotive body electronics integration.

Technical Context

The UPD78F0394GC-8EA-A implements the 78K0 CPU core - an 8-bit CISC architecture with minimum instruction cycle of 0.1 µs at 20 MHz (4.0–5.5 V), 0.2 µs at 10 MHz (2.7–5.5 V), or 0.4 µs at 5 MHz (1.8–5.5 V). It integrates dual power domains (VDD/LVDD, AVREF/AVSS) for analog and LCD subsystem isolation.

Its peripheral set includes a 16-bit timer (TM00), four 8-bit timers (TMH0/TMH1/TM50/TM51), watchdog timer (WDT) driven by dedicated 240 kHz ring oscillator, and LCD driver configurable for booster or ladder type with programmable voltage generation (VLC0–VLC2). UART6 supports LIN 2.0 physical layer compliance via slew-rate controlled output and sync-break detection.

Key Specifications

Pinout & Package

UPD78F0394GC-8EA-A is housed in a 64-pin QFP package (12 mm × 12 mm, 0.65 mm pitch), RoHS-compliant and rated for industrial temperature range.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit microcontroller applications.

Compared with UPD78F0394GC-8EA-A, R5F100PLGSP offers superior energy efficiency and modern toolchain support but demands firmware rework, while UPD78F0363GC-8EA-A provides zero-hardware-change compatibility at the cost of reduced Flash flexibility.

Availability

UPD78F0394GC-8EA-A is available at Aetrix Electronics and suitable for industrial HMI panels, automotive body control modules, smart energy meters, and portable medical diagnostics requiring stable component supply over extended production lifecycles.

Supply support for UPD78F0394GC-8EA-A 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 formed in 2010 through the merger of NEC Electronics and Renesas Technology, specializing in microcontrollers, analog, and power solutions for industrial, automotive, and infrastructure markets.

The UPD78F0394GC-8EA-A belongs to the 78K0/LE2 product line - designed specifically for cost-sensitive, display-integrated embedded systems requiring robust Flash reliability, low-power LCD driving, and LIN-ready serial interfaces in compact QFP packages.

FAQ

What is the maximum operating frequency of the UPD78F0394GC-8EA-A and under what voltage conditions?

The UPD78F0394GC-8EA-A achieves a maximum operating frequency of 20 MHz when supplied at 4.0–5.5 V using the high-speed system clock (external crystal or internal 8 MHz ring oscillator with PLL-like prescaling). At 2.7–4.0 V, max frequency drops to 10 MHz, and at 1.8–2.7 V, it is limited to 5 MHz - all supported by the same 78K0 CPU core with corresponding instruction cycle times of 0.1 µs, 0.2 µs, and 0.4 µs respectively.

Does the UPD78F0394GC-8EA-A support LIN bus communication natively?

Yes, the UPD78F0394GC-8EA-A includes UART6 - a dedicated LIN-compliant interface meeting ISO 17987-4 electrical specifications. It features built-in sync-break generation and detection, dominant timeout monitoring, and slew-rate controlled output, enabling direct connection to LIN transceivers without external level-shifting or timing compensation circuitry.

What LCD configuration options does the UPD78F0394GC-8EA-A support?

The UPD78F0394GC-8EA-A supports up to 20 segment × 4 common LCD drive with selectable booster-type or ladder-type voltage generation. Its VLC0–VLC2 outputs provide programmable bias voltages (VLC0 = 3×VLC2, VLC1 = 2×VLC2), allowing direct connection to static or multiplexed LCDs without external charge pumps or resistor networks.

Is on-chip debug functionality available on the UPD78F0394GC-8EA-A?

Yes, the UPD78F0394GC-8EA-A includes full on-chip debug support via a single-wire interface compatible with Renesas E1/E20 emulators. This allows non-intrusive program execution control, real-time register and memory access, and Flash programming - all without requiring dedicated debug pins beyond the standard reset and clock lines.

What are the power supply domains and their roles in the UPD78F0394GC-8EA-A?

The UPD78F0394GC-8EA-A uses three distinct power domains: VDD/LVDD for digital logic and LCD driver circuits, AVREF/AVSS for analog peripherals (ADC, internal reference), and separate LVDD pin for LCD bias generation. This separation minimizes noise coupling between analog measurements and display switching transients, improving ADC accuracy and LCD contrast stability.