1.77 inch Raspberry Pi Display ST7735S SPI

Product Introduction

The HTM-H017A3-SPI-V0 is a 1.77 inch Raspberry Pi Display LCD module designed and manufactured by HOTHMI. This display utilizes the ST7735S driver IC and features a resolution of 128×3RGB×160, delivering detailed and vividly colored imagery. The module supports 3-wire/4-wire SPI serial interfaces, effectively conserving microcontroller pin resources for rapid integration. It operates at 2.5V to 3.3V and achieves a high brightness of 850 cd/m² under constant current testing, ensuring excellent clarity and visibility in varied lighting conditions.

The display offers a 12 o’clock viewing direction, incorporates a complete drive circuit, and has a compact form factor. Additionally, it demonstrates strong environmental resilience, with an operating temperature range of -20℃ to +70℃ and a storage temperature range of -30℃ to +80℃. Whether you are developing smart home instruments, portable handheld devices, or seeking a cost-effective color display for Raspberry Pi or microcontrollers like Arduino, STM32, or ESP32, this 1.77 inch Raspberry Pi Display meets your technical requirements seamlessly.

Key Highlights

• Ultra-High Brightness for Sunlight Readability
  Unlike ordinary color screens on the market that offer only 300–500 cd/m², this 1.77 inch Raspberry Pi Display module achieves 850 cd/m² under constant current test conditions. This high-brightness design provides strong resistance to ambient light interference, ensuring that screen content remains vivid, crisp, and legible even outdoors or under direct sunlight. It is an ideal choice for outdoor portable devices.
• Industrial-Grade ST7735S Driver
  At the core of this 1.77 inch Raspberry Pi Display is the well-known ST7735S driver IC, which not only delivers stable performance and excellent power efficiency but also benefits from extensive community support. Whether using Python libraries on Raspberry Pi (e.g., st7735 library, Pillow graphics library) or the Adafruit_ST7735 framework on Arduino, you can achieve plug-and-play functionality, significantly reducing debugging time.
• Wide Temperature Tolerance
  Engineered with industrial-grade quality, this 1.77 inch Raspberry Pi Display LCD module offers exceptional environmental adaptability. Its operating temperature ranges from -20℃ to +70℃, and storage temperature spans -30℃ to +80℃. From in-vehicle terminals in summer heat to industrial monitoring equipment in winter cold, it maintains high refresh rates and long-term stable operation.

Pin Definition

This 1.77 inch Raspberry Pi Display module provides two rows of pin headers (CN1 and CN2) on the PCB, with a standard 2.54mm pitch.

Application Scenarios

Thanks to its top-tier backlight brightness and lightweight SPI communication, this LCD module demonstrates versatile value within the Raspberry Pi ecosystem and beyond, serving as a true multi-purpose 1.77 inch Raspberry Pi Display:

• Smart Home IoT Control Panels: Embedded into wall switches, smart thermostats, or gateway status monitors, this 1.77 inch Raspberry Pi Display shows real-time room temperature, humidity, WiFi status, and UI icons.
• Maker/Open-Source Hardware and Raspberry Pi Mini Terminals: Paired with Raspberry Pi Zero / 4B / 5 to create a mini Linux console desktop, using this 1.77 inch Raspberry Pi Display as a hardware monitoring sub-screen (displaying CPU usage, memory, temperature, and network bandwidth).
• Portable Handheld Measurement Instruments: Ultra-high brightness ensures excellent visibility in field engineering, geological surveys, vehicle-mounted thickness gauges, infrared thermometers, and other handheld testing devices.
• Retro Handheld Game Consoles: The 128×160 resolution is perfectly suited for emulating 8-bit/16-bit retro games (e.g., GameBoy emulators), and this 1.77 inch Raspberry Pi Display paired with Raspberry Pi achieves smooth frame rates.
• Medical and Industrial Instrument Displays: Serves as a status and alert display on small medical monitors, precision lab power supplies, and automated production line sensor nodes.

Technical Q&A

Q1: Does this 1.77 inch Raspberry Pi Display support direct 5V logic level input from systems like Arduino Uno?

A: Direct connection of 5V logic signals to the data pins is not supported. According to the official specifications, the operating voltage (VCI) of this module has an upper limit of 3.3V. Although some modules with onboard voltage regulators can accept 5V VCC power input, the logic input pins (SCK, SDA, CS, D/C) are still only 3.3V-tolerant.
If you are using a Raspberry Pi (which natively uses 3.3V logic), direct connection works perfectly. However, for 5V microcontrollers like Arduino Uno, you must insert a level shifter (e.g., 74HC4050 or a dedicated bidirectional level converter) on the data lines. Otherwise, prolonged exposure to high voltage will damage the built-in ST7735S driver IC.

Q2: Can the backlight pin (BLEN) be left floating? How can dimming be implemented?

A: Leaving the BLEN pin floating is not recommended. Although some PCB designs include an internal pull-up, a floating pin is susceptible to electromagnetic noise, which can cause backlight flickering.

Always-On Connection: If you do not need brightness adjustment and want the screen to maintain its maximum 850 cd/m² brightness at all times, you can directly connect the BLEN pin to the 3.3V power positive.

Dynamic Dimming: For adjustable brightness, connect the BLEN pin to a PWM-capable GPIO pin on the Raspberry Pi (e.g., GPIO 18). By programming the hardware PWM duty cycle from 0% to 100%, you can smoothly adjust the backlight of this 1.77 inch Raspberry Pi Display, reducing glare at night or significantly lowering power consumption in battery-powered applications.

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.