LSI0128HG002B | 1.28 inch TFT-LCD | 240x240 | 4-SPI | GC9A01
1. Executive Summary & Product Positioning
The LSI0128HG002B is a 1.28-inch transmissive type a-Si TFT-LCD (amorphous silicon thin film transistor liquid crystal display) module developed by 立信(万安)智显科技有限公司 (Lesson Smart Dispaly Technology Co., Ltd). It is composed of a TFT-LCD panel, a driver circuit, and a backlight unit. The panel size is 1.28 inch and the resolution is 240RGB×240, the panel can display up to 262K colors.
Product Positioning: Designed for a wide range of compact applications requiring a small, circular-shaped display with a simple 4-wire SPI interface. With its small outline (35.2 × 37.24 × 0.5 mm), integrated GC9A01 driver IC, and free viewing direction, it is ideally suited for smart wearables, small handheld devices, home appliances, and other embedded systems that need a low-pin-count display solution.
2. Detailed Product Overview & Architecture
The module's architecture is designed for simple integration and robust performance. The primary components include:
- TFT-LCD Panel: 1.28-inch diagonal, a-Si TFT active matrix, transmissive display mode. The resolution is 240(RGB) × 240 pixels with a square active area of 32.4(W) x 32.4(H) mm.
- Driver IC: The module uses the GC9A01 driver IC.
- Backlight Unit (B/L): A white LED edge-lit backlight unit (2-chip white LED). The typical forward current (If) is 40mA with a forward voltage (Vf) of 3.0V to 3.4V.
- Mechanical Construction: COG (Chip-on-Glass) + FPC. The module outline dimensions are 35.2(H) x 37.24(V) x 0.5(T) mm.
- Interface: The module communicates via a 15-pin FPC connector. The main display interface is a 4-SPI (Serial Peripheral Interface).
3. Exhaustive Technical Specifications
3.1 General & Mechanical Specifications
| Item | Specification |
| Display Size (Diagonal) | 1.28 inches |
| Resolution (Dots) | 240RGB × 240 |
| Display Technology | a-Si TFT, Transmissive |
| Module Construction | COG+FPC |
| Color Depth | 262K Colors |
| Viewing Direction | FREE |
| Pixel Arrangement | RGB Vertical Stripe |
| Pixel Pitch (H×V) | 0.135(H) x 0.135(V) mm |
| Active Area (H×V) | 32.4(W) x 32.4(H) mm |
| Outline Dimension (H×V×T) | 35.2(H) x 37.24(V) x 0.5(T) mm |
| Interface | 4-SPI |
| Backlight Configuration | White LED (2 LED Chip), 40mA |
| Driver IC | GC9A01 |
| Operating Temperature | -20°C to +70°C |
| Storage Temperature | -30°C to +80°C |
3.2 Electrical Specifications
3.2.1 DC Characteristics (Ta=25°C)
| Parameter | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Supply Voltage | VDD (IOVCC=1.65V~3.3V) | 2.5 | 2.8 | 3.3 | V |
| Input High Voltage | VIH | 0.7xIOVCC | - | IOVCC | V |
| Input Low Voltage | VIL | 0 | - | 0.3xIOVCC | V |
| Output High Voltage | VOH | 0.8xIOVCC | - | - | V |
| Output Low Voltage | VOL | - | - | 0.2xIOVCC | V |
| I/O Leakage Current | ILI | -1 | - | 1 | uA |
| Normal Operation Current | IOP | - | 5.5 | 7.5 | mA |
| Sleep Current | ISLP | - | 70 | 200 | uA |
3.2.2 Backlight LED Characteristics
The backlight uses a 2-chip White LED configuration.
| Parameter | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Forward Current (IFBL) | IFBL | 30 | 40 | 50 | mA |
| Forward Voltage (VF) | VF | 3.0 | 3.2 | 3.4 | V |
3.3 Interface Pin Map (15-Pin Connector)
The module uses a 15-pin connector. The pinout integrates the 4-SPI interface, power supply, and backlight signals.
| Pin No. | Symbol | Function Description |
|---|---|---|
| 1 | LEDK | Cathode of Backlight |
| 2 | SDA | Serial Input Data (MOSI) |
| 3 | LEDA | Anode of Backlight |
| 4 | SCL | Clock Signal (SCLK) |
| 5 | NC | No Connection |
| 6 | RESET | Chip Reset Signal (Low Active) |
| 7 | IOVCC | Supply Voltage for Interface Pins (+1.8V or +2.8V) |
| 8 | CS | Chip Select (Low Active) |
| 9 | TE | Tearing Effect Output Signal |
| 10 | GND | Ground |
| 11 | RS | Data/Command Select Signal (DCX) |
| 12 | GND | Ground |
| 13 | VCI | Supply Voltage for Analog Circuit (+2.8-3.3V) |
| 14 | GND | Ground |
| 15 | VCI | Supply Voltage for Analog Circuit (+2.8-3.3V) |
3.4 Environmental and Compliance Standards
| Item | Specification |
| Storage Temperature | -30°C ~ +80°C |
| Operating Ambient Temperature | -20°C ~ +70°C |
| RoHS Compliance | Yes (EU RoHS + Halogen-Free) |
3.5 Inspection Standards
The specification defines detailed inspection standards for the AQL (Acceptable Quality Level).
- Major Defect AQL: 0.65 (Covers functional defects like no display, missing lines, backlight not working).
- Minor Defect AQL: 1.5 (Covers appearance defects like spots, dots, lines, scratches, and glass defects).
Example Point Defect Criteria (within View Area):
- Black/White spots with diameter (Φ) ≤ 0.1mm: Ignored (no serial contamination).
- Black/White spots with 0.1mm < Φ ≤ 0.15mm: Max 3 allowed (Area A).
- Black/White spots with 0.15mm < Φ ≤ 0.25mm: Max 2 allowed (Area A).
- Black/White spots with Φ > 0.25mm: Not allowed (Area A).
4. Application Guidelines & Critical Notes
When integrating the LSI0128HG002B module, engineers must adhere to the specific guidelines outlined in the specification to ensure optimal performance and reliability.
- Power Supply: The module requires a main supply voltage (VCI) of 2.8V to 3.3V for the analog circuit and an IO supply (IOVCC) of 1.65V to 3.3V for the interface pins. These can be connected together if a single 2.8V or 3.3V rail is available.
- 4-SPI Interface: This is a standard 4-wire SPI interface. The control lines are CS (Chip Select), SCL (Clock), SDA (Data), and RS (Data/Command). The RESET pin must be toggled correctly after power-up to initialize the GC9A01 driver IC.
- Backlight Driver (External): The backlight requires an external constant current driver set to 40mA (Typ). The forward voltage of the 2-chip LED is approximately 3.2V. The LED Anode (LEDA) and Cathode (LEDK) pins are brought out separately for easy connection to an external driver.
- Mechanical Integration: The module outline dimensions are 35.2(H) x 37.24(V) x 0.5(T) mm. The viewing area is 32.4(W) x 32.4(H) mm. The FPC is a PI+FPC construction with a total thickness of 0.2±0.03mm. The unmarked tolerance is ±0.2mm.
- Handling Precautions: The module uses a glass LCD panel and CMOS LSI. Handle with care to avoid breakage and protect against static electricity. Do not expose to condensation, strong mechanical shock, or fixed patterns for extended periods to prevent image sticking.
- RoHS Compliance: This module is designed to comply with EU RoHS and halogen-free requirements.
5. Conclusion & Design-In Support
The LSI0128HG002B from Lesson Smart Display Technology is a compact, power-efficient, and easy-to-use 1.28-inch TFT-LCD module. Its combination of a standard 4-SPI interface, the well-supported GC9A01 driver IC, a small form factor, and wide temperature range makes it an ideal choice for a wide variety of compact display applications.
For design-in support, it is strongly recommended to:
- Obtain and review the full Product Specification (Revision 1.0) for the complete set of electrical parameters, timing diagrams, and the mechanical outline drawing.
- Design the power supply to provide a single 2.8V or 3.3V rail for both VCI and IOVCC, and design a constant current backlight driver (40mA at ~3.2V).
- Develop firmware using the GC9A01 driver IC initialization sequence and SPI communication protocol, which is well-documented in public libraries.
- Contact the manufacturer for evaluation kits, sample requests, and technical support during the design-in phase.
This module is engineered to deliver reliable and vibrant display performance for small-scale embedded systems.
