Product Main Title:
LS028I26-S-V1: 2.83-Inch IPS TFT LCD Module, 240x320 Resolution, 262K Colors, SPI Interface
Product Subtitle / Keywords:
2.83 Inch Display, QVGA 240x320 Resolution, Transmissive a-Si IPS TFT, SPI Interface, COG+FPC+B/L, 262K Colors, Wide Viewing Angle, JD9853 Driver, RoHS Compliant
Comprehensive Technical Specification & Application Guide
1. Executive Summary & Product Positioning
The LS028I26-S-V1, developed by LESSON (Wan'an) Zhixian Technology Co., Ltd., is a 2.83-inch transmissive amorphous Silicon TFT-LCD module featuring IPS (In-Plane Switching) technology for wide viewing angles. This product specification book serves as the definitive technical document, defining its structural composition (COG+FPC+B/L), mechanical dimensions, absolute maximum ratings, detailed electrical characteristics, 4-line SPI (Serial Peripheral Interface) timing, and comprehensive electro-optical performance. It delivers a QVGA resolution of 240(RGB)×320 with 262K-color display capability. The document provides essential parameters for system integration and includes critical mechanical design guidelines for housing integration. Engineers should use this document to guide electrical design, SPI driver development, and mechanical assembly, paying particular attention to the recommended bezel and foam cutout clearances to ensure optimal visual performance and long-term reliability.
2. Detailed Product Overview & Architecture
- Core Technology: Transmissive-type a-Si TFT-LCD with IPS technology.
- Display Characteristics: Capable of displaying up to 262 thousand colors.
- Module Construction: COG (Chip-On-Glass) + FPC (Flexible Printed Circuit) + B/L (Backlight Unit). Composed of a TFT-LCD panel, a driver circuit (JD9853), and a backlight unit.
- Interface: 4-line SPI (Serial Peripheral Interface).
- Input Data: SPI.
- Viewing Direction: Free (IPS – wide viewing angle).
- Drive IC: JD9853.
- Display Mode: Transmissive type, Active matrix TFT.
3. Exhaustive Technical Specifications
3.1 Mechanical & Physical Specifications
| Item | Specification | Unit |
|---|---|---|
| Module size (H×V×D) | 50.0 × 69.1 × 2.3 | mm |
| Active area (H×V) | 43.2 × 57.6 | mm |
| Number of dots / Resolution | 240(RGB) × 320 | pixel |
| Panel Size (Diagonal) | 2.83 | inch |
3.2 Electrical & Interface Specifications
3.2.1 Absolute Maximum Ratings
| Item | Symbol | Min | Max | Unit | Remark |
|---|---|---|---|---|---|
| Supply voltage | VCC | -0.3 | 4.6 | V | Note1, Note2 |
| I/O Supply voltage | IOVCC | -0.3 | 4.0 | V | Note1, Note2 |
| Operating temperature | TOPR | -20 | 70 | °C | Note1, Note2 |
| Storage temperature | TSTR | -30 | 80 | °C | Note1, Note2 |
Notes (from general spec conventions):
- Note1: Stresses beyond these ratings may cause permanent damage.
- Note2: Functional operation under these conditions is not implied.
3.2.2 Electrical Characteristics (DC)
| Item | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Supply voltage (Main) | VCC | 2.4 | 2.8 | 3.3 | V |
| I/O Supply voltage | 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 Pin Description (24-pin FPC)
| PIN NO. | Symbol | I/O | Description |
|---|---|---|---|
| 1 | RESET | I | Reset pin. |
| 2 | SPI_SCL | I | Serial clock pin. |
| 3 | SPI_D/C | I | Command and Data select pin. |
| 4 | SPI_CS | I | Chip select pin. |
| 5 | VDD2.8V | P | Power supply (2.8V). |
| 6 | VDDI2.8V | P | Power supply (2.8V, likely I/O). |
| 7 | SPI_SDA | I/O | Serial data input/output pin. |
| 8 | GND | P | Ground. |
| 9 | LEDK | P | Power for LED backlight cathode. |
| 10 | LEDA | P | Power for LED backlight anode. |
| 11 | GND | P | Ground. |
| 12-23 | NC | Not Connected. | |
| 24 | TE | O | Tearing effect output pin to synchronize MPU to frame writing. |
3.2.4 Interface Timing Characteristics
A. SPI Interface AC Characteristics (4-line SPI):
Conditions: Not explicitly stated, typically Ta=25°C.
| Signal | Symbol | Parameter | Min. | Max. | Unit | Description |
|---|---|---|---|---|---|---|
| CSX | tcss | Chip select setup time (Write) | 15 | -- | ns | |
| CSX | tcsh | Chip select hold time (Write) | 15 | -- | ns | |
| CSX | tcss | Chip select setup time (Read) | 60 | -- | ns | |
| CSX | tcsh | Chip select hold time (Read) | 65 | -- | ns | |
| DCX | tas | Address (D/CX) setup time | 10 | -- | ns | |
| DCX | tah | Address (D/CX) hold time | 10 | -- | ns | |
| SCL (write) | twc | Write cycle time | 16 | -- | ns | |
| SCL (write) | twrh | Control pulse "H" duration | 7 | -- | ns | |
| SCL (write) | twrl | Control pulse "L" duration | 7 | -- | ns | |
| SCL (read) | trc | Read cycle time | 150 | -- | ns | |
| SCL (read) | trdh | Control pulse "H" duration (Read) | 60 | -- | ns | |
| SCL (read) | trdl | Control pulse "L" duration (Read) | 60 | -- | ns | |
| SDI/SDO (write) | tds | Data setup time | 7 | -- | ns | |
| SDI/SDO (write) | tdt | Data hold time | 7 | -- | ns | |
| SDO (read) | tracc | Read access time | 20 | -- | ns | |
| SDO (read) | tod | Output disable time | 25 | -- | ns |
B. Reset Input Timing:
| Symbol | Parameter | Related pins | Min. | Max. | Unit | Note |
|---|---|---|---|---|---|---|
| t_RW | Reset pulse width | RESX | 10 | - | µs | |
| t_RT | Reset complete time | - | - | 5 | ms | When reset in Sleep In mode |
| t_RT | Reset complete time | - | - | 120 | ms | When reset in Sleep Out mode |
- Spike Rejection: The RESET line has built-in spike rejection. Pulses shorter than 20ns are rejected; a pulse wider than 10µs is recognized as a valid reset.
3.2.5 Backlight Unit
- Configuration: 4 Chip-White LEDs in Parallel.
- Drive Condition (Typical): Forward Current (I_F) = 80 mA; Forward Voltage (V_f) = 3 V.
3.3 Optical & Electro-Optical Characteristics (Ta=25°C)
| Item | Symbol | Condition | Min. | Typ. | Max. | Unit | Remark |
|---|---|---|---|---|---|---|---|
| Response Time | Tr + Tf | θx = θy = 0 | -- | -- | 35 | ms | Note 1 |
| Contrast Ratio | CR | θx = θy = 0 | 1000 | 1500 | -- | -- | Note 2 |
| Transmittance | T% | θx = θy = 0 | 4.5 | 4.8 | -- | % | |
| Color Chromaticity (White) | W x | θx = θy = 0 | -- | 0.301 | -- | -- | CIE1931 |
| Color Chromaticity (White) | W y | θx = θy = 0 | -- | 0.320 | -- | -- | CIE1931 |
| Viewing Angle (CR>10) | θT, θB, θL, θR | -- | -- | 85 | -- | Deg. | Note 3 |
Notes (Interpreted from context):
- Response time is the sum of rise and fall time.
- Contrast ratio measured with a standard pattern.
- Viewing angles (Top, Bottom, Left, Right) are symmetrical (85° typical) due to IPS technology.
4. Application Guidelines & Critical Notes
- Intended Use: Industrial HMIs, consumer electronics, medical devices, instrumentation—applications requiring a medium-sized color display with wide viewing angles and a simple SPI interface.
- Critical Design Considerations:
- Mechanical Integration (CRITICAL): The document provides explicit design rules for the end-product housing:
- Bezel Opening (Visible Area): Should be designed 0.3mm smaller per side than the module's active area (AA: 43.2x57.6mm) to hide the non-active edges.
- Foam Gasket Cutout: Should be 0.6mm larger per side than the module's viewing area (VA) to avoid applying pressure on the display surface, which can cause optical defects (Mura).
- Avoid Metal Contact: The TP (Touch Panel, if applicable) edges must not contact metal conductors.
- Dual Power Supplies: Provide stable VCC (2.4-3.3V) for the main logic and IOVCC (1.65-3.3V) for the I/O interface. Ensure they are within the recommended operating range.
- SPI Interface: The host MCU's SPI peripheral must be configured to meet the setup, hold, and pulse width timings specified in section 3.2.4. The presence of a TE (Tearing Effect) pin allows for optimized frame buffer updates.
- Reset Circuit: Ensure the RESET pin receives a low pulse of at least 10µs during initialization. Note the different recovery times (5ms vs 120ms) depending on the display's sleep state.
- Backlight Drive: Design a constant-current driver circuit capable of supplying 80mA typical current to the parallel LED string. Account for the typical 3V forward voltage.
- Temperature Ranges: Operate within -10°C to +60°C and store within -20°C to +70°C.
- Mechanical Integration (CRITICAL): The document provides explicit design rules for the end-product housing:
- Handling & Compliance: The module is ROHS compliant. Observe standard ESD precautions during handling.
5. Conclusion & Design-In Support
The LS028I26-S-V1 specification details a robust 2.83-inch IPS SPI display module. Its key strengths are the wide 85-degree viewing angles afforded by IPS technology, clear mechanical integration guidelines, and a standard 4-line SPI interface compatible with most microcontrollers. The main design focus should be on precise mechanical housing design to leverage the IPS viewing benefits without inducing pressure-related artifacts, and on configuring the SPI master to meet the provided AC timing. By following the electrical and mechanical specifications, this module provides a reliable and visually consistent display solution for a wide range of embedded applications.
