LSC0395I05-R-V1: 3.95-Inch TFT LCD Module, 480×480 Resolution, RGB Interface, IPS Display
Product Subtitle / Keywords
3.95 Inch Display, 480(RGB)×480 Resolution, a-Si TFT-LCD Module, Transmissive, IPS Display, 16.7M Display Colors, COG+FPC+B/L+CTP Module Type, 8-Bit RGB Interface, SPI Control Interface, Operating Temperature -20°C to +70°C, Storage Temperature -30°C to +80°C, Supply Voltage VCC=2.8V (Typ), IOVCC=1.8V (Typ), Driver IC ST77922, Viewing Direction Free (IPS), Backlight IF=40mA, Module Type COG+FPC+B/L+CTP, RoHS Compliant, Spec Rev 1.0, Lesson Smart Display Technology Co., Ltd.
1. Executive Summary & Product Positioning
The LSC0395I05-R-V1, developed by Lesson Smart Display Technology Co., Ltd. (立信(万安)智显科技有限公司), is a transmissive type a-Si TFT-LCD (amorphous silicon thin film transistor liquid crystal display) module, which is composed of a TFT-LCD panel, a driver circuit and a backlight unit. The panel size is 3.95 inch and the resolution is 480(RGB)*480, the panel can display up to 16.7 M colors. The module type is COG+FPC+B/L+CTP.
This product specification (Revision 1.0) serves as the definitive technical document, defining the module's physical features (including display mode, format, input data, and viewing direction), mechanical specification (including module size, number of dots, and active area), outline dimension (including detailed mechanical drawings and notes on operating/storage temperature, backlight configuration, and driver IC), absolute maximum ratings (for supply voltage, operating temperature, and storage temperature), electrical characteristics (including recommended operating conditions for power supplies and logic levels), module function description (including pin description, block diagram, and timing characteristics for SPI, RGB, and Reset interfaces), and electro-optical characteristics.
The document provides the core parameters necessary for system integration into standard 3.95-inch square display applications. The unequivocal recommendation for engineers is to strictly adhere to the mechanical and electrical specifications 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) module, which is composed of a TFT-LCD panel, a driver circuit and a backlight unit.
- Display Resolution: Square format: 480(RGB) × 480 pixel array.
- Display Mode: IPS (In-Plane Switching) with "Free" viewing direction (Grayscale Inversion). Active matrix TFT, Transmissive type.
- Module Construction: COG (Chip-On-Glass) + FPC (Flexible Printed Circuit) + B/L (Backlight) + CTP (Capacitive Touch Panel).
- Interface Type: The module uses an 8-bit RGB Interface for pixel data combined with a 4-Wire SPI Interface for command/register configuration. It also includes a dedicated touch panel I²C interface.
- Power Architecture: Requires dual power supplies: VCC (2.8V Typ for the core/analog/booster) and IOVCC (1.8V Typ for the I/O interface).
- Backlight: "Five series and two parallel white LED" configuration. The driving condition is specified as IF=40mA (20mA/LED), VF=15~16V.
- Touch Panel: The module includes a Capacitive Touch Panel (CTP) interface. The dedicated CTP pins (TP_INT, TP_SDA, TP_SCL, TP_RESET) are provided. The I²C interface is used for communication.
- Driver IC: ST77922.
- Supplier: 立信(万安)智显科技有限公司 (Lesson Smart Display Technology Co., Ltd).
3. Exhaustive Technical Specifications
3.1 Mechanical & Physical Specifications
| Item | Specification | Unit |
|---|---|---|
| Model | LSC0395I05-R-V1 | - |
| Display Size (Diagonal) | 3.95 | inch |
| Resolution | 480(RGB) × 480 | pixels |
| Display Type / Mode | Transmissive a-Si TFT-LCD, Active matrix TFT, IPS | - |
| Module Type | COG+FPC+B/L+CTP | - |
| Display Colors | 16.7M | colors |
| Viewing Direction (Grayscale Inversion) | Free (IPS) | - |
| Input Data | 8bit-RGB | - |
| Driver IC | ST77922 | - |
| Supplier | 立信(万安)智显科技有限公司 (Lesson Smart Display Technology Co., Ltd) | - |
3.2 Interface & Electrical Specifications
3.2.1 Absolute Maximum Ratings (From Section 5)
| Item | Symbol | Min | Max | Unit |
|---|---|---|---|---|
| Supply voltage | VCC | -0.3 | 4.6 | V |
| Supply voltage | IOVCC | -0.3 | 4.6 | V |
| Operating temperature | TOPR | -20 | 70 | °C |
| Storage temperature | TSTR | -30 | 80 | °C |
3.2.2 Recommended Operating Conditions (From Section 6)
| Item | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Supply voltage (Analog/Digital System) | VCC | 2.65 | 2.8 | 3.3 | V |
| Supply voltage (I/O) | IOVCC | 1.65 | 1.8 | 3.3 | 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 (Partial, From Section 7-2)
The module uses a 40-pin FPC connector which integrates the LCM, backlight, and CTP interface signals.
| PIN NO. | Symbol | I/O | Description |
|---|---|---|---|
| 1 | LEDA | P | LED ANODE |
| 2, 3 | LEDK | P | LED CATHODE |
| 5 | VCI | P | Power Supply for Analog, Digital System and Booster Circuit. |
| 9 | SDA | I | SPI Data signal |
| 10 | SCK | I | SPI Clock signal |
| 11 | CS | I | SPI Chip select signal |
| 12 | PCLK | I | RGB dot clock signal |
| 13 | DE | I | RGB data enable signal |
| 14 | VS | I | RGB frame synchronizing signal |
| 15 | HS | I | RGB line synchronizing signal |
| 16-23 | DB0 - DB7 | I | RGB interface data bus. |
| 35 | TP_INT | I | Touch screen interrupt. |
| 36 | TP_SDA | I | I2C interface data pin. |
| 37 | TP_SCL | I | I2C interface clock pin. |
| 38 | TP_RESET | I | External reset for TP. |
| 39 | IOVCC | P | Power Supply (1.8V-3.3V) |
3.3 Timing Characteristics
3.3.1 RGB Interface Timing (From Section 7.4.4)
Key parameters for the RGB interface (VDDI=1.65 to 3.3V, VDD=2.65 to 3.3V, Ta=25 °C):
| Signal | Parameter | MIN | MAX | Unit |
|---|---|---|---|---|
| DOTCLK | DOTCLK Cycle Time | 30 | - | ns |
| DOTCLK | Rise/Fall time | - | 10 | ns |
| DB | PD Data Setup Time | 15 | - | ns |
| DB | PD Data Hold Time | 15 | - | ns |
3.3.2 Serial Interface (SPI) Timing (From Section 7.4.2)
Key parameters for the 3-line serial interface (VDDI=1.65 to 3.3V, VDD=2.65 to 3.3V, Ta=25 °C):
| Signal | Parameter | MIN | MAX | Unit |
|---|---|---|---|---|
| SCL | Serial clock cycle (Write) | 16 | - | ns |
| SCL | Serial clock cycle (Read) | 150 | - | ns |
| SDA (DIN) | Data setup time | 7 | - | ns |
| SDA (DIN) | Data hold time | 7 | - | ns |
3.3.2 Reset Timing (From Section 7.4.7)
Key parameters for the reset signals:
| Related Pins | Parameter | MIN | MAX | Unit |
|---|---|---|---|---|
| RESX | Reset pulse duration | 10 | - | us |
| RESX | Reset cancel | - | 120 | ms |
| TP_RESX | Reset pulse duration | 10 | - | us |
| TP_RESX | Reset cancel | - | 100 | ms |
4. Application Guidelines & Critical Notes
Intended Use
- Standard 3.95-inch square display applications (e.g., smart home devices, industrial controls, handheld instruments).
- Systems requiring a 480x480 resolution display with an 8-bit RGB interface and SPI command interface.
- Applications requiring a built-in capacitive touch panel (CTP) with an I²C interface.
Critical Design Considerations
- Dual Power Supply (VCC=2.8V for Core, IOVCC=1.8V for I/O): The module requires a stable 2.8V supply for the core/analog circuitry and a separate 1.8V supply for the I/O interface. The logic thresholds (VIL, VIH) are referenced to IOVCC.
- Hybrid Interface (RGB + SPI): The module uses an 8-bit RGB interface for pixel data (PCLK, DE, VS, HS, DB0-DB7) and a separate 4-wire SPI bus (CS, SCK, SDA) for register/command configuration. These must be driven concurrently.
- External Backlight Driver (40mA @ ~15.5V Series/Parallel): The backlight consists of 5 series strings with 2 LEDs in parallel per string, requiring a constant current driver capable of delivering 40mA at a forward voltage of 15-16V.
- I²C Capacitive Touch Panel Interface: The CTP uses an I²C interface (TP_SDA, TP_SCL) with a dedicated reset pin (TP_RESET) and an interrupt output (TP_INT).
- IPS Display with Wide Viewing Angle: The display uses IPS technology, providing "Free" viewing direction with no grayscale inversion.
- Temperature Range (-20°C to +70°C Operating): A standard consumer/industrial temperature range.
- ESD and Handling: Standard ESD precautions must be observed during handling and assembly due to the sensitive electronic and glass components.
Handling & Compliance
- Observe standard ESD precautions during handling and assembly.
- The module contains fragile glass – handle with care. Avoid mechanical stress on the active area or FPC.
- Do not attempt to disassemble or modify the LCD module.
- The module is RoHS compliant.
5. Conclusion & Design-In Support
The LSC0395I05-R-V1 specification details a compact 3.95-inch square (480×480) IPS TFT LCD module with a transmissive display, an 8-bit RGB interface for video data, and an integrated capacitive touch panel — a versatile and practical choice for embedded applications requiring a high-quality square display solution.
Key Strengths
- Square Format IPS Display: The 1:1 aspect ratio and wide IPS viewing angles are ideal for unique GUI layouts (e.g., round or square watch faces, smart home panels).
- Separate RGB and SPI Buses: Separating the high-speed video data (RGB) from the command/control (SPI) simplifies the driver software architecture and can improve display update performance.
- Integrated Capacitive Touch Panel (I²C): Provides a complete touch display solution without needing an external touch controller.
- High Color Depth: True 16.7M color support enables rich and vibrant image reproduction.
- Detailed Technical Documentation: Comprehensive specs facilitate rapid integration.
Main Design Focus
- The critical design tasks are providing dual power supplies (VCC=2.8V, IOVCC=1.8V) with proper decoupling, implementing a constant-current LED backlight driver (40mA at ~15.5V), driving the host processor's 8-bit RGB interface (PCLK, DE, VS, HS, DB0-DB7) with correct timing, initializing the display driver via the 4-wire SPI bus (CS, SCK, SDA), and initializing and communicating with the touch controller over I²C (TP_SDA, TP_SCL, TP_INT, TP_RESET).
- Supporting requirements: Connect all ground pins. Ensure the RESET pin is driven low for a proper initialization sequence (minimum 10µs pulse).
This module is a reliable and practical choice for engineers designing embedded systems that require a square-format IPS display with touch and a dedicated high-speed pixel interface.
