2.8 inch LCD Screen RTP ST7789V For Arduino

Product Overview

The HTM-H028A1-MCU-V02 is a high-quality 2.8-inch TFT LCD Screen module designed by HOTHMI. This display features a resolution of 240×3RGB×320 and is built around the advanced ST7789V driver IC, delivering a full-viewing-angle visual experience with excellent color consistency. With an operating voltage range of 2.6V to 5.0V, support for MCU 8-bit or 16-bit parallel interfaces, and an integrated drive circuit, this LCD Screen achieves a brightness level of 450 cd/m² under constant current testing for outstanding display performance. Engineered for industrial-grade and demanding environments, the module offers wide temperature tolerance, operating from -20°C to +70°C and storing from -30°C to +80°C. It is specifically designed for high-reliability applications including industrial control, medical monitoring, smart home systems, and portable handheld terminals.

Product Highlights and Technical Advantages

• Full Viewing Angle Experience
  This LCD Screen adopts a full-viewing-angle design. Unlike conventional displays that suffer from color distortion or black-white inversion when viewed off-axis, the HTM-H028A1-MCU-V02 maintains excellent contrast and color saturation consistency from top, bottom, left, and right viewing directions.
• Powerful ST7789V Driver IC
  The integrated ST7789V driver chip is one of the most capable controllers for small-sized TFT LCD Screen modules. It features a built-in 240x320x18-bit display data RAM, enabling hardware-based true-color display of up to 262K colors without requiring external frame buffers. Its optimized power management and internal circuit architecture significantly reduce overall power consumption and simplify the software driver development for the host MCU.
• Multiple Parallel Interface Compatibility
  To suit various host controller architectures, this LCD Screen natively supports MCU 8-bit or 16-bit parallel bus interfaces. In 16-bit mode, which is ideal for high-speed screen refresh and smooth animation, data throughput is effectively doubled. In 8-bit mode, GPIO pin usage is greatly reduced for systems with limited I/O resources. This flexible interface configuration allows developers to freely switch between high performance and low pin count according to project requirements.
• 450 cd/m² Brightness with Constant Current Testing
  With a brightness rating of 450 cd/m², this LCD Screen undergoes rigorous constant current testing to ensure uniform, flicker-free backlight illumination. Even under strong indoor lighting or bright factory floor conditions, text and graphics remain clearly visible.
• Industrial-Grade Wide Temperature Range
  Designed for harsh operating environments, this LCD Screen demonstrates exceptional durability. Its TFT operating temperature spans -20°C to +70°C, while storage temperature extends from -30°C to +80°C. Whether deployed in hot outdoor enclosures during summer or in freezing industrial settings during winter, the module maintains stable 24/7 operation, significantly reducing failure rates caused by component aging.
• Integrated Resistive Touch Panel
  The product structure not only includes the TFT liquid crystal layer but also seamlessly integrates a resistive touch panel. In industrial scenarios where factory operators wear gloves or where equipment is exposed to water droplets and dust, resistive touch technology offers inherent interference resistance compared to capacitive screens, ensuring every tap and swipe is accurately registered.

Pin Definition

The HTM-H028A1-MCU-V02 uses a 34-pin 1.0mm pitch header connector.

Typical Application Scenarios

This fully featured LCD Screen, with its environmental robustness and standard interface, is widely deployed across the following vertical industries:

• Industrial Human-Machine Interface Panels
  On CNC machines, PLC automation control cabinets, and variable frequency drive parameter display panels, the wide-temperature operation and high noise immunity of the 8080 parallel bus are fully utilized. The 450 cd/m² brightness ensures excellent data readability under high-power factory lighting.
• Medical Electronic Monitoring Equipment
  The high-sensitivity resistive touch combined with 240×320 resolution perfectly meets the display requirements of bedside call units, portable pulse oximeters, and multi-parameter ECG monitors. The backlight, verified through constant current testing, effectively prevents flicker that could interfere with infrared sensing accuracy in precision medical devices.
• Portable Handheld Instruments
  Thanks to the highly integrated ST7789V driver and ultra-low sleep current consumption, this LCD Screen is an ideal choice for battery-powered devices such as infrared thermometers, digital oscilloscopes, laser rangefinders, and air quality detectors.
• Smart Home and IoT Terminals
  Smart wall-mounted gateways, thermostat panels, elevator floor indicator panels, and various environmental monitoring terminals all benefit from the full viewing angle display, allowing users to clearly read screen data from any angle across the living room or corridor.

Technical Q&A 

Q1: The ST7789V driver supports both 8-bit and 16-bit MCU interfaces. What are the differences in hardware design and software driver implementation?

A1:Hardware level: In 8-bit mode, only data lines DB0 through DB7 on the header are used; the remaining higher data pins can be left floating or grounded. In 16-bit mode, all 16 lines from DB0 to DB15 must be fully connected to the controller’s I/O ports.

Performance and driver level: When transmitting image data in software, 16-bit mode sends a complete RGB565 pixel in a single write clock cycle (one WR pulse). In contrast, 8-bit mode requires splitting the pixel into high-byte and low-byte, requiring two write pulses. Therefore, 16-bit mode provides double the refresh rate, making it ideal for animation-rich interfaces, while 8-bit mode significantly saves host MCU pin resources.

Q2: How can I adjust the backlight brightness of this LCD Screen via the pin header?

A2: The backlight drive circuit of this display incorporates a high-quality constant current test design. On pin 24 (BL) of the header, users can either apply a constant high level to achieve 100% full brightness, or connect this pin to an MCU GPIO pin with PWM capability. By adjusting the PWM duty cycle (recommended frequency range: 1kHz to 10kHz), smooth 0% to 100% stepless brightness and power consumption adjustment can be achieved without damaging the LEDs.

From minor concept tweaks to full custom redesign & development, our engineering team offers end-to-end technical support. Feel free to contact us for custom display demands or technical issues during product selection.