Product Subtitle / Keywords:
2.8 Inch Display, 240(RGB)×320 Resolution, Transmissive a-Si TFT-LCD, 4-Line SPI Interface, COG+FPC+B/L, 262K Colors, 10-Pin, 50×69.2×2.3 mm, 300 cd/m² Brightness, 800:1 Contrast Ratio, 25ms Response Time, 12 O'Clock Viewing Direction, -20°C~70°C Operating Temperature
1. Executive Summary & Product Positioning
The LS028I01-S-V1, developed by Lixin (Wan'an) Intelligent Display Technology Co., Ltd. (立信(万安)智显科技有限公司), is a 2.8-inch transmissive amorphous Silicon TFT-LCD (a-Si TFT-LCD) module.
This product specification (Revision 1.0, Module Type: COG+FPC+B/L) serves as the definitive technical document, defining its structural composition (COG+FPC+B/L), physical features, mechanical dimensions, absolute maximum ratings, detailed electrical characteristics, complete 4-Line SPI (Serial Peripheral Interface) pinout and timing, and comprehensive electro-optical performance. It delivers a resolution of 240(RGB)×320 with 262K-color display capability.
The document provides the core parameters necessary for system integration into compact embedded display applications. The unequivocal recommendation for engineers is to strictly adhere to the electrical specifications, interface timing, and mechanical tolerances described herein to ensure reliable performance and compatibility.
2. Detailed Product Overview & Architecture
- Core Technology: Transmissive-type a-Si TFT-LCD (amorphous silicon thin film transistor liquid crystal display).
- Display Mode: Active matrix TFT, Transmissive type.
- Display Format: Graphic 240(RGB)×320 Dot-matrix.
- 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, and a backlight unit.
- Input Data: 4-line serial interface.
- Viewing Direction (Grayscale Inversion): 12 O'Clock.
- Connector Pin Count: 10-Pin.
- Approval Status: ☑ Approved Product Specification only (as per signature block).
3. Exhaustive Technical Specifications
3.1 Mechanical & Physical Specifications
| Item | Specification | Unit |
|---|---|---|
| Module size (H×V×D) | 50 × 69.2 × 2.3.3 | mm |
| Active area (H×V) | 43.2 × 57.6 | mm |
| Number of dots / Resolution | 240(RGB) × 320 | pixel |
| Panel Size (Diagonal) | 2.8 | inch |
Critical Mechanical Design Notes (from outline dimension drawing):
- Display Type: Normally Black.
- Viewing Direction: 12 O'Clock.
- Number of Pixels: 240*(RGB)*320.
- LCD Manufacturer: BOE 2.8 IPS.
- Interface: 4 Line SPI (LCD).
- Operating Temperature: -30°C ~ 70°C.
- Storage Temperature: -20°C ~ 70°C.
- LCM Brightness: 300 cd/m².
- Backlight Circuit: 80mA, 3.2V.
- General Tolerance: ±0.20 mm.
- FPC Total Thickness: PI+FPC=0.3±0.03mm.
- Backlight Thickness: 2.30mm.
- Module Total Thickness (H): 0.1 (不含背胶).
- FPC Bend: The FPC is shipped in a specific bent configuration (FPC弯折图).
- Unit: MM.
3.2 Electrical & Interface Specifications
3.2.1 Absolute Maximum Ratings
(Not explicitly provided in the extracted document excerpt; refer to Section 5 of the full specification.)
3.2.2 Electrical Characteristics (DC – Recommended Operating Conditions)
| Item | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Supply voltage | VCC | — | 2.8 | — | V |
| Supply voltage | IOVCC | — | 1.8 | — | V |
| Input Voltage (L level) | VIL | 0 | — | 0.3*IOVCC | V |
| Input Voltage (H level) | VIH | 0.7*IOVCC | — | IOVCC | V |
3.2.3 Pin Description (10-pin FPC)
| PIN NO. | Symbol | Description |
|---|---|---|
| 1 | RESET | Reset pin |
| 2 | LEDA | LED power anode |
| 3 | LEDK | LED power cathode |
| 4 | VCC | Power supply |
| 5 | GND | Ground |
| 6 | RS | Command and Data select pin |
| 7 | NC | No Connect |
| 8 | SCK | Serial clock pin |
| 9 | SDA | Serial data input/output PIN |
| 10 | CS | Chip select pin |
Interface Summary:
- 4-Line Serial Interface: Uses SCK (Serial Clock), SDA (Serial Data), RS (Data/Command), CS (Chip Select), and RESET (Reset) for communication.
- Backlight: Dedicated LEDA (Anode, Pin 2) and LEDK (Cathode, Pin 3) pins.
- Power: VCC (Pin 4) for main logic, GND (Pin 5) for ground.
- Unused Pins: Pin 7 is NC — leave floating.
3.2.4 Serial Interface Timing Characteristics (4-line serial)
Conditions: VDDI=1.65 to 3.3V, VDD=2.4 to 3.3V, AGND=DGND=0V, Ta=25°C.
| Signal | Symbol | Parameter | MIN | MAX | Unit | Description |
|---|---|---|---|---|---|---|
| CSX | TCS | 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 | TSCC | Chip select hold time (read) | 65 | — | ns | |
| CSX | TCHW | Chip select "H" pulse width | 40 | — | ns | |
| SCL | TSCYCW | Serial clock cycle (Write) | 16 | — | ns | -write command & data ram |
| SCL | TSHW | SCL "H" pulse width (Write) | 7 | — | ns | -write command & data ram |
| SCL | TSLW | SCL "L" pulse width (Write) | 7 | — | ns | -write command & data ram |
| SCL | TSCYCR | Serial clock cycle (Read) | 150 | — | ns | -read command & data ram |
| SCL | TSHR | SCL "H" pulse width (Read) | 60 | — | ns | -read command & data ram |
| SCL | TSLR | SCL "L" pulse width (Read) | 60 | — | ns | -read command & data ram |
| D/CX | TDSS | D/CX setup time | 10 | — | ns | |
| D/CX | TCHH | D/CX hold time | 10 | — | ns | |
| SDA (DIN) | TSDS | Data setup time | 7 | — | ns | |
| SDA (DIN) | TSDH | Data hold time | 7 | — | ns | |
| DOUT | TACC | Access time | 10 | 50 | ns | For maximum CL=30pF For minimum CL=8pF |
| DOUT | TOH | Output disable time | 15 | 50 | ns | For maximum CL=30pF For minimum CL=8pF |
3.2.5 Backlight Unit
| Item | Specification | Unit |
|---|---|---|
| LED Circuit | — | — |
| Drive Condition | 80mA, 3.2V | — |
Backlight Circuit Diagram (from document):
LEDA → [Backlight Circuit] → LEDK
IF = 80mA
VF = 3.2V
3.3 Optical & Electro-Optical Characteristics (Ta=25°C)
| Item | Symbol | Condition | Min. | Typ. | Max. | Unit | Remark |
|---|---|---|---|---|---|---|---|
| Response time | Tr + Tf | θx = θy = 0 | — | 25 | — | ms | Note 1 |
| Contrast Ratio | CR | θx = θy = 0 | — | 800 | — | — | Note 2 |
| Viewing angle | θT | CR > 10 | — | 80 | — | Deg. | Note 3 |
| Viewing angle | θB | CR > 10 | — | 80 | — | Deg. | Note 3 |
| Viewing angle | θL | CR > 10 | — | 80 | — | Deg. | Note 3 |
| Viewing angle | θR | CR > 10 | — | 80 | — | Deg. | Note 3 |
Notes (from document):
Note 1: Definition of Response Time
The response time is defined as the following figure and shall be measured by switching the input signal for "black" and "white". This definition is valid for a normally black display. For a normally white display the opposite definition applies.
- Tr (Rise Time): Time from 10% to 90% of optical response.
- Tf (Fall Time): Time from 90% to 10% of optical response.
- Tr + Tf = Total Response Time.
Note 2: Definition of Contrast Ratio
Contrast ratio (CR) is defined mathematically by the following formula:Contrast Ratio = Luminance measured when LCD on the "White" state / Luminance measured when LCD on the "Black" state
Note 3: Definition of Viewing Angle
Viewing angle is the angle at which the contrast ratio is greater than 10. Angles are determined for the horizontal or x axis and the vertical or y axis with respect to the z axis which is normal to the LCD surface.
Note 4: Backlight Circuit
- Circuit diagram: LEDA → [Backlight] → LEDK
- Drive condition: 80mA, 3.2V
3.4 Version Record
(Not explicitly provided in the extracted document excerpt; refer to Section 9 of the full specification.)
4. Application Guidelines & Critical Notes
Intended Use
- Smartwatches, fitness trackers, and other wearable devices
- IoT display nodes and smart home controls
- Miniature handheld instruments
- Any application requiring a compact display with standard resolution
Critical Design Considerations
-
Interface (4-Line Serial SPI): This module uses a 4-line serial SPI interface for communication. The host MCU must have at least 5 GPIOs (SCK, SDA, RS, CS, RESET) to drive the display.
-
Power Supply:
- Provide stable VCC (2.8V typical) for the main logic (connected to Pin 4).
- Provide stable IOVCC (1.8V typical) for the I/O interface.
- The backlight requires a constant-current LED driver connected to LEDA (Anode, Pin 2) and LEDK (Cathode, Pin 3), set to 80 mA at approximately 3.2V.
-
Mechanical Integration:
- Module Outline: 50mm (H) × 69.2mm (V) × 2.3mm (D).
- Active Area: 43.2mm × 57.6mm.
- FPC: The module uses a 10-pin FPC.
- FPC Bend: The FPC has a designated bend area — follow the intended bend direction for installation.
-
Viewing Angle Characteristics:
This module provides a viewing direction of 12 O'Clock:- Top (12 o'clock): 80° (Typ)
- Bottom (6 o'clock): 80° (Typ)
- Left (9 o'clock): 80° (Typ)
- Right (3 o'clock): 80° (Typ)
-
Optical Performance:
- Response Time: 25ms (Typ) – fast enough for most GUI applications.
- Contrast Ratio: 800 (Typ) – good contrast performance.
- LCM Brightness: 300 cd/m² (Typ) – high brightness for good readability.
-
Temperature Limits:
- Operating Temperature: -30°C to +70°C.
- Storage Temperature: -20°C to +70°C.
Handling & Compliance
- Observe standard ESD precautions during handling and assembly.
- The module contains fragile glass and a 10-pin FPC – handle with care.
- Avoid bending the FPC sharply, especially near the connector interface.
- The module has a total thickness of 2.3mm – be careful when handling to avoid flexing.
5. Conclusion & Design-In Support
The LS028I01-S-V1 specification details a standard 2.8-inch display module with a 4-line serial interface and 10-pin connector — an excellent choice for cost-sensitive, simple display applications.
Key Strengths:
-
Standard Resolution (240x320): Suitable for simple icons, text, and basic UIs.
-
Standard 4-Line Serial Interface: Requires only 5 GPIOs for communication, simplifying integration.
-
High Brightness: 300 cd/m² (Typ) ensures good readability in indoor conditions.
-
Fast Response Time: 25ms (Typ) – suitable for most GUI applications.
-
Wide Operating Temperature Range: -30°C to +70°C for operation and -20°C to +70°C for storage.
-
Standard 10-pin FPC: The 10-pin FPC provides a robust connection interface.
Main Design Focus:
- The critical design task is properly implementing the serial interface timing to ensure reliable communication.
- Supporting requirements:
- Provide stable VCC (2.8V typical) and IOVCC (1.8V typical) power.
- Provide a constant-current backlight driver set to 80 mA at 3.2V.
- Mechanical integration — the module outline is 50mm × 69.2mm × 2.3mm.
- FPC connector — verify the 10-pin FPC.
This module is an excellent choice for designs where cost, size, and simplicity are the primary concerns, such as simple numeric displays, status indicators, or low-cost IoT nodes.
