Tags & Keywords
#TFT-LCD #TN #SPI #2.8inch #240x320 #262KColors #COG #Transmissive #EmbeddedDisplay #IndustrialHMI #PortableDevice #MCUInterface #RoHS #Backlight #LESSON #SmartDisplay
Introduction
This document is the official product specification for the LS028T34-S-V1, a 2.8-inch transmissive a-Si TFT-LCD module developed by LESSON Smart Display Technology Co., Ltd. Featuring QVGA resolution (240x320), 262K colors, and a TN (Twisted Nematic) panel, this module is designed as a cost-effective and reliable display solution for embedded systems. With its simple 4-line SPI interface and comprehensive specifications covering mechanical, electrical, and optical characteristics, it serves as a practical choice for a wide range of applications including consumer electronics, industrial controls, and portable devices.
Key Specifications
- Brand & Model: LESSON Smart Display LS028T34-S-V1
- Screen Size: 2.8 inches (diagonal)
- Active Area: 43.2 mm (H) × 57.6 mm (V)
- Driver IC: ST7789P3 (as indicated in the Physical Features section)
- Display Technology: Transmissive type a-Si TFT-LCD
- Display Mode: Active matrix TFT, Transmissive type, TN (Twisted Nematic)
- Module Type: COG + FPC + B/L (Chip-On-Glass, Flexible Printed Circuit, Backlight Unit)
- Display Resolution: 240(RGB) × 320 pixels (QVGA)
- Display Colors: Up to 262K Colors
- Module Outline Dimensions: 50.0 mm (H) × 69.1 mm (V) × 2.3 mm (D)
- Interface: 4-line Serial Interface (SPI) (Pins: CS, SCL, SDA, DC, RESET)
- Input Data: SPI
- Viewing Direction: 6 O'clock (TN characteristic)
- Supply Voltages:
- VCC (Main Power): 2.4V ~ 3.3V (Typical: 2.75V)
- IOVCC (I/O Power): 1.65V ~ 3.3V (Typical: 1.8V)
- Absolute Maximum Ratings:
- VCC / IOVCC: -0.3V to +4.6V
- Operating Temperature (T_OPR): -20°C to +70°C
- Storage Temperature (T_STR): -30°C to +80°C
- Backlight: 4-chip white LED in parallel (Drive condition: I_F=80mA, V_F=3V Typical)
- Environmental Compliance: RoHS Compliant
General Description
The LS028T34-S-V1 is a versatile and economical display module built around a standard TN panel with a 6 o'clock viewing direction. Its 2.8-inch size with QVGA resolution is a popular format for many embedded applications. The module is controlled by the ST7789P3 driver IC, which is accessed via a standard 4-line SPI interface (Chip Select CS, Serial Clock SCL, Serial Data SDA, Data/Command DC, and Reset). This interface minimizes the required host MCU GPIO pins.
The specification includes detailed SPI timing characteristics for write operations, defining parameters like chip select setup/hold time and serial clock pulse widths. It also details the power on/off sequence and reset timing for different sleep modes. The document provides critical mechanical design guidelines, such as recommending the housing opening to be 0.3mm smaller per side than the active area (VA area) and ensuring the backlight foam gasket opening is at least 0.6mm larger per side. It also warns that the touch panel (TP) edges must not contact metal conductors.
Pin Description
| PIN NO. | Symbol | I/O | Description |
|---|---|---|---|
| 1 | LEDK | P | Backlight LED Cathode |
| 2 | LEDA | P | Backlight LED Anode |
| 3 | RESET | I | Reset (Active Low) |
| 4 | CS | I | SPI Chip Select (Active Low) |
| 5 | SCL | I | SPI Serial Clock |
| 6 | SDA | I/O | SPI Serial Data Input/Output |
| 7 | DC | I | SPI Data/Command Selection |
| 8 | GND | P | Ground |
| 9 | VCC | P | Main Power Supply (2.75V Typ.) |
| 10 | IOVCC | P | I/O Interface Power (1.8V Typ.) |
Application Scenarios
- Industrial HMIs: Control and status panels for machinery, automation systems.
- Portable Consumer Devices: Handheld instruments, smart home controllers, portable multimedia.
- Medical and Healthcare Devices: Patient monitors, diagnostic equipment interfaces.
- Point-of-Sale (POS) Systems: Customer-facing displays for small terminals.
- Automotive Aftermarket: Displays for car audio systems or diagnostic tools.
- IoT and Embedded Devices: General-purpose user interface for various controllers.
Conclusion
The LESSON Smart Display LS028T34-S-V1 is a cost-effective, thoroughly documented, and easy-to-integrate display solution. Its use of the common ST7789P3 driver with a simple SPI interface, clear electrical and timing specifications, and detailed mechanical integration notes makes it a practical choice for product developers seeking a reliable QVGA display for a wide range of applications.
