This document describes the electrical and optical environmental specifications of the Noritake Itron VFD module GU256x128D-3900. The module features a 256x128 dot graphic display, 5V supply, high brightness blue-green display, operating temperature range of -40°C to +85°C, high-speed 8-bit parallel interface, and asynchronous serial interface.
The GU256x128D-3900 is a 256 × 128 dot graphic vacuum fluorescent display module that includes the glass panel, 5 V supply drivers, micro‑controller ICs, refresh RAM and high‑brightness blue‑green illumination. It offers a high‑speed 8‑bit parallel interface compatible with 5 V TTL/CMOS logic and an asynchronous serial interface supporting up to 38.4 kbaud.
Electrical specifications list a 5.0 VDC supply (±5 %), typical current draw of 850 mA, a display area of 115.05 × 57.45 mm, and a luminance of 500 cd/m². The module operates from –40 °C to +85 °C, with humidity tolerance of 20‑80 % RH, and provides defined RS232 and logic voltage levels for reliable communication. A full command set for cursor control, display clearing, character download and mode selection is included.
| Display Area | 115.05 x 57.45 mm |
|---|---|
| Power Supply Voltage (VCC) | 5.0 VDC ±5 % |
| Power Supply Current (Icc) | 850 mA (typ) |
| Dot Size / Pitch | 0.3 × 0.3 mm / 0.45 × 0.45 mm |
| Luminance | 500 cd/m² (typ) |
| Colour of Illumination | Blue‑Green |
| Operating Temperature | -40 °C to +85 °C |
| Storage Temperature | -40 °C to +85 °C |
| Operating Humidity (non‑condensing) | 20 % to 80 % RH @ 25 °C |
| Power‑on Rise Time | < 100 ms |
The module operates from –40 °C to +85 °C.
The RS232 high input voltage (VIH) is a minimum of 3.0 VDC.
A 5.0 VDC supply with a tolerance of ±5 % is required.