Introduction
This document details the product specification for the LS024I40-S-V1, a 2.4-inch transmissive a-Si TFT-LCD module from LESSON Smart Display Technology Co., Ltd. Featuring a QVGA resolution of 240(RGB)x320 pixels, 262K color capability, and an IPS panel for wide viewing angles, this module is designed as a versatile and reliable display solution. With its simple 4-line SPI interface and comprehensive specifications covering mechanical, electrical, and electro-optical characteristics, it serves as an excellent choice for a wide range of embedded systems, portable devices, and consumer electronics requiring a compact, high-quality graphical interface.
Key Specifications
- Brand & Model: LESSON Smart Display LS024I40-S-V1
- Screen Size: 2.4 inches (diagonal)
- Active Area: 36.72 mm (H) × 48.96 mm (V)
- Driver IC: ST7789P3 (as indicated in the Physical Features section)
- Display Technology: Transmissive type a-Si TFT-LCD (Amorphous Silicon Thin Film Transistor Liquid Crystal Display)
- Display Mode: Active matrix TFT, Transmissive type, IPS (In-Plane Switching)
- 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: 42.72 mm (H) × 60.26 mm (V) × 2.25 mm (D)
- Interface: 4-line Serial Interface (SPI) (Pins: CS, SCL, SDA, DC, RESET). Also includes a TE (Tearing Effect) output pin.
- Input Data: 8BIT-MCU (via SPI interface)
- Viewing Direction: Free (IPS)
- Luminance: Not explicitly stated in the provided electro-optical table.
- Contrast Ratio: 1200:1 (Typical), 900:1 (Minimum)
- Response Time (Tr+Tf): 35 ms (Typical), 40 ms (Maximum)
- Transmittance: 4.7% (Typical)
- White Point Chromaticity (CIE1931): Wx: 0.308 (Typ.), Wy: 0.339 (Typ.)
- Viewing Angle (CR > 10): 85° (Typical, all directions: Top, Bottom, Left, Right)
- Supply Voltages:
- VCC (Logic & Analog Power): 2.4V ~ 3.3V (Typical: 2.75V)
- IOVCC (I/O Interface Power): 1.65V ~ 3.3V (Typical: 1.8V)
- Absolute Maximum Ratings:
- VCC / IOVCC: -0.3V to +4.6V / +4.0V
- Operating Temperature (T_OPR): -20°C to +70°C
- Storage Temperature (T_STR): -30°C to +80°C
- Backlight: 4-chip white LED in series (Drive condition: I_F=20mA, V_F=12V Typical)
General Description
The LS024I40-S-V1 is a well-rounded display module built around a wide-viewing-angle IPS (In-Plane Switching) panel, providing a consistent 85-degree viewing cone from all directions. Its 2.4-inch size with QVGA resolution is a popular and versatile 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 and simplifies firmware development.
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 (Sleep Out, Sleep In), which are critical for reliable initialization and power management. The electro-optical characteristics are clearly defined, showing a high typical contrast ratio of 1200:1 and fast response time.
A significant portion of the document is dedicated to a comprehensive quality inspection and defect criteria system based on GB/T 2828-2003. This system meticulously defines Acceptable Quality Levels (AQL) and details major/minor defects for the LCD panel (glass defects, cracks), FPC (copper peel, impurities), tapes (shift, missing), glue application, and electrical performance (no display, missing lines, Mura, dots, scratches). This provides clear guidelines for manufacturing consistency and product acceptance.
Pin Description
| PIN NO. | Symbol | I/O | Description |
|---|---|---|---|
| 1 | GND | P | Ground |
| 2 | VCI | P | Power supply for LCD drive |
| 3 | IOVCC | P | I/O Interface power supply |
| 4 | TE | O | Tearing effect output signal for frame sync |
| 5 | SDA | I/O | Serial data input/output |
| 6 | DC | I | Data/Command selection pin |
| 7 | SCL | I | Serial clock input |
| 8 | CS | I | Chip select input (Active Low) |
| 9 | RESET | I | Reset input (Active Low) |
| 10 | GND | P | Ground |
| 11 | LEDA | P | Backlight LED Anode |
| 12 | LEDK | P | Backlight LED Cathode |
Application Scenarios
This reliable IPS SPI module is suitable for numerous applications requiring a robust display:
- Industrial HMIs: Control and status panels for machinery, automation systems, and test equipment.
- Portable Consumer Devices: Handheld instruments, smart home controllers, and portable multimedia devices.
- Medical and Healthcare Devices: Patient monitors, diagnostic equipment, and wearable health sensors.
- Point-of-Sale (POS) Systems: Customer-facing displays for small kiosks or payment terminals.
- Automotive Aftermarket: Displays for car audio systems, rear-view cameras, or diagnostic tools.
- IoT and Embedded Devices: General-purpose user interface for various controllers and gateways.
Conclusion
The LESSON Smart Display LS024I40-S-V1 is a robust, thoroughly documented, and easy-to-integrate display solution. Its combination of an IPS panel for wide viewing angles, the common ST7789P3 driver with a simple SPI interface, clear electrical and timing specifications, and an extensive set of quality control criteria makes it a dependable choice for product developers. It is particularly well-suited for applications where consistent visual quality, reliable operation, and straightforward microcontroller integration are paramount.
