128×64 COG Display FSTN+ ST7565R

I. Product Detailed Introduction

The HTG12864-140-31W-28C05-V01, launched by HOTHMI, is a high-performance monochrome dot-matrix 128×64 COG Display LCD module. This product employs an FSTN positive transflective display mode, offering a graphic dot-matrix resolution of 128×64 pixels and supporting a 6 o’clock viewing direction to deliver a wide, clear, and high-contrast visual presentation. Thanks to its transflective characteristics, it can display clearly by reflecting sunlight in extremely bright outdoor environments, while in dark conditions, the built-in side-lit white LED backlight can be activated to maintain excellent visibility.

The 128×64 COG Display module integrates an advanced ST7565R controller driver IC, operates at a standard 3.3V supply voltage, and features ultra-compact outer dimensions of merely 28.55×20.10×4.3mm, making it exceptionally space-efficient and specifically designed for compact and portable devices. In terms of communication interfaces, it offers remarkable flexibility, supporting both 8-bit parallel interfaces (6800/8080 timing) and 4-wire SPI serial interfaces with compatible switching, greatly simplifying connection solutions with various microcontrollers.

Additionally, this 128×64 COG Display module is equipped with a low-power white LED backlight circuit (operating current 30mA, typical voltage 3.0V) and maintains stable operation across a wide temperature range from -20°C to +70°C, making it widely applicable in communication equipment, portable instruments and meters, smart home devices, and various industrial control applications that demand robust display performance.

II. Key Highlights of the 128×64 COG Display

• Ultra-thin COG Packaging, Custom-Designed for Miniature Devices
  Compared with conventional COB display modules, this product leverages COG technology to dramatically minimize thickness and peripheral hardware footprint. With an outer area of 28.55 × 20.10 mm and a total thickness of less than 4.3mm, it can be seamlessly embedded into various handheld test pens, portable medical instruments, and ultra-compact card-style devices.
• Integrated Low-Power ST7565R Advanced Controller
  The 128×64 COG Display module is powered by a high-performance single-chip LCD driver IC – the ST7565R. This chip integrates a complete display data RAM, an internal oscillator circuit, a DC-DC voltage conversion circuit, and a voltage regulator. This means users do not need to design complex negative voltage generators or high-precision contrast adjustment circuits on the mainboard; a single display chip handles everything.
• Robust All-Weather Environmental Adaptability
  This product offers high-standard industrial-grade environmental resilience, with an operating temperature range of -20°C to +70°C and a storage temperature range of -30°C to +80°C. Moreover, with its FSTN transflective material, it never blacks out under direct sunlight, effectively solving the common issue of insufficient outdoor brightness found in TFT screens.

III. 28-Pin Terminal Functions Description

The 128×64 COG Display module adopts a 28-pin FPC flexible cable interface.

IV. Typical Product Application Scenarios

Thanks to its stringent control over space, power consumption, and environmental factors, this 128×64 COG Display LCD module finds extensive applications across various industrial and consumer sectors:

• Portable Handheld Instruments and Meters: Electronic measuring pens, high-precision digital multimeters, infrared thermometers, pocket-sized environmental detectors (such as PM2.5 monitors and radiation dosimeters).
• Industrial Automation and Intelligent Control: PLC small display terminals, DIN-rail monitoring modules in equipment rooms, servo drive parameter setting panels, industrial flow meters.
• Medical and Health Monitoring Equipment: Blood glucose meters, portable pulse oximeters, heart rate monitors, parameter display panels for small intelligent physiotherapy devices.
• Smart Home and Communication Terminals: Smart thermostats, wireless intercom displays, network switch status indicator panels, high-end audio system front panels.
• Sports and Automotive Micro-Devices: Bicycle smart cyclocomputers, in-vehicle OBD diagnostic mini-screens, outdoor portable GPS track loggers.

V. Core Technical FAQ for 128×64 COG Display

Q1: I would like to save I/O pins on my controller. How do I configure this module for serial SPI mode?

A1: You simply need to connect Pin 28 (PS) to a low level (VSS) and Pin 27 (C86) to a low level (VSS) in your hardware circuit routing or breadboard setup. After configuration:
The original parallel bus will be converted to a serial bus.
Connect your MCU’s SPI data output line (MOSI/SDO) to the module’s DB7 (SI) pin.
Connect your MCU’s SPI clock line (SCK/SCL) to the module’s DB6 (SCL) pin.
Pins /CS1 (Chip Select), /RES (Reset), and A0 (Command/Data toggle) still need to be reserved and connected to your MCU’s general-purpose I/Os for control.

Q2: What are the advantages of an FSTN transflective screen compared to ordinary STN yellow-green or STN blue screens?

A2: FSTN incorporates a high-precision optical compensation film between the liquid crystal layers. Its core advantages include:
Complete elimination of color cast: Ordinary STN displays exhibit distinct yellow-green or deep-blue tones, whereas FSTN achieves pure monochrome black-and-white display with significantly enhanced image contrast.
Transflective all-weather operation: Ordinary transmissive screens tend to wash out or become illegible under outdoor sunlight, while reflective screens are unusable in dark environments. The transflective screen perfectly combines both: outdoors, it directly reflects sunlight and becomes clearer as ambient light intensifies; indoors and at night, it utilizes the white LED backlight for transmissive viewing, delivering a perfect reading experience across all lighting conditions and scenarios.