LS0128I14-S-V1 | 1.28 inch TFT-LCD | 240x240 | SPI | COG+FPC+B/L
1. Executive Summary & Product Positioning
The LS0128I14-S-V1 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 Display 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 240(RGB)*240, the panel can display up to 262k colors.
Product Positioning: Designed for compact, wearable, and small-scale display applications requiring a moderate resolution SPI interface. With its 1.28-inch diagonal, square 240x240 resolution, and low pin-count SPI interface, it is ideally suited for smartwatches, wearable devices, small IoT interfaces, and other portable human-machine interfaces.
2. Detailed Product Overview & Architecture
The module's architecture is designed for compact integration. 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 an active area of 32.4 × 32.4 mm.
- Driver IC: The module uses the GC9A01 driver IC, which supports a 4-line SPI interface.
- Backlight Unit (B/L): A white LED edge-lit backlight unit. The backlight configuration is 2 Chip-White LED. The driving condition is If=40mA; Vf=3.0~3.4V.
- Mechanical Construction: COG (Chip-on-Glass) + FPC + B/L. The module outline dimensions are 35.6 (H) × 37.74 (V) × 1.6 (D) mm.
- Interface: The module communicates via a 15-pin FPC connector. The main display interface is a 4-Line Serial SPI.
3. Exhaustive Technical Specifications
3.1 General & Mechanical Specifications
| Item | Specification |
| Display Size (Diagonal) | 1.28 inches |
| Resolution (Dots) | 240(RGB) × 240 |
| Display Technology | Active Matrix TFT, Transmissive, a-Si |
| Module Construction | COG+FPC+B/L |
| Color Depth | 262K Colors |
| Optimum Viewing Direction | Free |
| Input Data Interface | 4-Line SPI |
| Driver IC | GC9A01 |
| Active Area (H×V) | 32.4 × 32.4 mm |
| Module Size (H×V×D) | 35.6 × 37.74 × 1.6 mm |
| Operating Temperature | -10°C to +60°C |
| Storage Temperature | -20°C to +70°C |
3.2 Electrical Specifications
3.2.1 Absolute Maximum Ratings
| Parameter | Symbol | Min | Max | Unit |
|---|---|---|---|---|
| Supply voltage (VCC) | VCC | -0.3 | 4.6 | V |
| Supply voltage (IOVCC) | IOVCC | -0.3 | 4.6 | V |
| Operating Temperature | TOPR | -10 | 60 | °C |
| Storage Temperature | TSTR | -20 | 70 | °C |
3.2.2 DC Characteristics (Ta=25°C)
| Parameter | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Supply Voltage (VCC) | VCC | 2.5 | 2.8 | 3.3 | V |
| Supply Voltage (IOVCC) | IOVCC | 1.65 | 1.8 | 3.3 | V |
| Input Voltage (Low Level) | VIL | 0 | -- | 0.3*IOVCC | V |
| Input Voltage (High Level) | VIH | 0.7*IOVCC | -- | IOVCC | V |
3.2.3 Backlight LED Characteristics
The backlight uses a 2 Chip-White LED configuration. The driving condition is If=40mA; Vf=3.0~3.4V.
3.3 Interface & Pin Map (15-Pin FPC)
The module uses a 15-pin FPC connector. The pinout integrates the SPI interface, power supply, and backlight signals.
| Pin No. | Symbol | I/O | Description |
|---|---|---|---|
| 1 | LEDK | P | Cathode of Backlight |
| 2 | SDA | I/O | Serial input data |
| 3 | LEDA | P | Anode of Backlight |
| 4 | SCL | I | Clock signal |
| 5 | NC | - | Open |
| 6 | RESET | I | Chip reset signal |
| 7 | IOVCC | P | Supply voltage to the interface pins (+1.8V or +3.3V) |
| 8 | CS | I | Serial chip select |
| 9 | TE | O | Tearing effect output pin to synchronize MPU to frame writing, activated by S/W command |
| 10 | GND | P | Ground |
| 11 | RS | I | Data/command select signal |
| 12 | GND | P | Ground |
| 13 | VCI | P | Supply voltage to the analog circuit (+2.8-3.3V) |
| 14 | GND | P | Ground |
| 15 | VCI | P | Supply voltage to the analog circuit (+2.8-3.3V) |
3.4 Optical Specifications
Optical characteristics are measured at Ta=25°C, Normal viewing angle (Θ=0).
| Item | Symbol | Condition | Min | Typ | Max | Unit |
|---|---|---|---|---|---|---|
| Color Chromaticity (White) - CIE1931 | Wx, Wy | Θ=0 | Typ -0.02 | (0.347), (0.347) | Typ +0.02 | - |
| Color Chromaticity (Red) - CIE1931 | Rx, Ry | Θ=0 | Typ -0.02 | (0.644), (0.333) | Typ +0.02 | - |
| Color Chromaticity (Green) - CIE1931 | Gx, Gy | Θ=0 | Typ -0.02 | (0.325), (0.566) | Typ +0.02 | - |
| Color Chromaticity (Blue) - CIE1931 | Bx, By | Θ=0 | Typ -0.02 | (0.134), (0.124) | Typ +0.02 | - |
| Viewing Angle (All Directions) | ΘL, ΘR, ΘU, ΘD | CR > 10 | 80 | 85 | - | Deg. |
| Optima View Direction | - | - | - | Free | - | - |
3.5 Interface Timing Characteristics (4-Line SPI)
The module supports 4-Line SPI interface with the following key parameters (Test Condition: Ta = 25 °C, IOVCC=1.65V to 3.3V, VCI=2.5V to 3.3V, AGND=VSS=0V).
3.5.1 Write Cycle Timing
| Signal | Symbol | Min | Max | Unit |
|---|---|---|---|---|
| CSX (Chip select setup time) | tcss | 20 | - | ns |
| CSX (Chip select hold time - Read) | tcsh | 40 | - | ns |
| SCL (Serial Clock Cycle - Write) | twc | 10 | - | ns |
| SCL (SCL "H" Pulse Width - Write) | twrh | 5 | - | ns |
| SCL (SCL "L" Pulse Width - Write) | twrl | 5 | - | ns |
| D/CX (Setup time) | tas | 10 | - | ns |
| D/CX (Hold time - Write/Read) | tah | 10 | - | ns |
| SDA/SDI (Data setup time - Write) | tds | 5 | - | ns |
| SDA/SDI (Data hold time - Write) | tdh | 5 | - | ns |
3.5.2 Read Cycle Timing
| Signal | Symbol | Min | Max | Unit |
|---|---|---|---|---|
| SCL (Serial Clock Cycle - Read) | trc | 150 | - | ns |
| SCL (SCL "H" Pulse Width - Read) | trdh | 60 | - | ns |
| SCL (SCL "L" Pulse Width - Read) | trdl | 60 | - | ns |
| SDA/SDO (Access time - Read) | tacc | 10 | - | ns |
Note: The rising time and falling time (Tr, Tf) of input signal are specified at 15 ns or less. Logic high and low levels are specified as 30% and 70% of IOVCC for Input signals.
4. Application Guidelines & Critical Notes
When integrating the LS0128I14-S-V1 module, engineers must adhere to the specific guidelines outlined in the specification to ensure optimal performance and reliability.
- Power Supply (Dual Rail): The module requires two supply rails: VCI (2.8V to 3.3V) for the analog circuit and IOVCC (1.65V to 3.3V) for the I/O interface. The I/O voltage level must match the host's logic level.
- SPI Interface (4-Line): This is a standard 4-line serial SPI interface. The host processor must have a compatible SPI controller. The maximum SPI clock speed is defined by twc (Write) and trc (Read) parameters.
- Backlight Driver (External): The module provides separate LED Anode (LEDA) and Cathode (LEDK) pins. The backlight consists of 2 white LEDs with a typical forward voltage of 3.0 to 3.4V. An external driver is required.
- Mechanical Integration: The module outline dimensions are 35.6 × 37.74 × 1.6 mm. The FPC is designed for bending.
- Handling Precautions: The module uses a glass LCD panel. Handle with care to avoid breakage.
- RoHS Compliance: This module is designed to comply with RoHS directives.
5. Conclusion & Design-In Support
The LS0128I14-S-V1 from Lesson Smart Display Technology is a compact, efficient 1.28-inch TFT-LCD module. Its combination of a square 240x240 resolution, standard 4-line SPI interface, and free viewing angle makes it an excellent choice for a wide variety of wearable and small-scale 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, interface timing diagrams, and mechanical drawings.
- Design the power supply to provide both VCI and IOVCC rails. Design a constant current backlight driver (40mA at ~3.2V).
- Develop firmware using the standard SPI protocol for the GC9A01 driver IC.
- Contact the manufacturer for evaluation kits, sample requests, and technical support during the design-in phase.
This module is engineered to deliver reliable, clear display performance for compact electronic products.
