LS0395I18-R-V1 3.95 Inch TFT-LCD Module 480x480 16.7M Colors
1. Executive Summary & Product Positioning
The LS0395I18-R-V1 is a 3.95-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). The module 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 16.7M colors. This module features a COG (Chip-on-Glass) + FPC + B/L (Backlight) construction and is designed for a wide range of applications requiring a square-format, high-quality display. [1](@index-ref?id=1)
Product Positioning: This 3.95-inch square module is ideally suited for smart home devices, handheld instruments, wearable displays, and other embedded systems requiring a compact square display with vivid colors and wide viewing angles.
2. Detailed Product Overview & Architecture
The module's architecture integrates the display into a single, easy-to-integrate package. The primary components include:
- TFT-LCD Panel: 3.95-inch diagonal, a-Si TFT active matrix, transmissive, IPS (In-Plane Switching). Resolution is 480(RGB) × 480 pixels.
- Driver Circuit: The module integrates the ST7701P driver IC, communicating via 3-Line or 4-Line SPI (Serial Peripheral Interface).
- Backlight Unit (B/L): A white LED backlight. The typical driving condition is IF=200mA, Vf=3.0V (TYP), with a 10 Chip Parallel LED configuration.
- Mechanical Construction: COG (Chip-on-Glass) + FPC + B/L.
- Interface: The module communicates via a 40-pin FPC connector. The display interface is 3-Line / 4-Line SPI.
- Display Mode: Transmissive, IPS.
- Viewing Direction: ALL O'Clock (IPS).
- RoHS: All materials are compliant with RoHS standards.
3. Exhaustive Technical Specifications
3.1 General & Mechanical Specifications
| Item | Specification |
| Display Size (Diagonal) | 3.95 inches |
| Resolution (Dots) | 480(RGB) × 480 |
| Display Technology | Active Matrix TFT, Transmissive, a-Si, IPS |
| Module Construction | COG+FPC+B/L |
| Color Depth | 16.7M Colors |
| Input Data Interface | 3-Line / 4-Line SPI |
| Driver IC | ST7701P |
| Display Mode | Transmissive, IPS |
| Viewing Direction | ALL O'Clock (IPS) |
| Backlight Type | White LED (10 Chip Parallel) |
| LCM Outline (H×V×D) | 74.66 × 74.66 × 2.11 mm (Typ.) |
| Active Area (H×V) | 71.86 × 71.86 mm |
| Operating Temperature | -20°C to +70°C |
| Storage Temperature | -30°C to +80°C |
| Environmental Compliance | RoHS |
3.2 Absolute Maximum Ratings
Stress beyond those listed may cause permanent damage to the device.
| 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 |
3.3 Electrical Characteristics
3.3.1 Recommended DC Characteristics
Condition: VDDI=1.8V, VDD=2.8V, AGND=DGND=0V, Ta=25°C.
| Item | Symbol | Min | Typ | Max | Unit |
|---|---|---|---|---|---|
| Supply voltage | VCC | 2.5 | 2.8 | 3.3 | V |
| Supply voltage | 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 |
3.3.2 Backlight LED Characteristics
The backlight consists of a 10 Chip Parallel configuration of white LEDs. The typical driving condition is IF=200mA, Vf=3.0V (TYP).
| Parameter | Symbol | Typ | Unit |
|---|---|---|---|
| Forward Voltage | Vf | 3.0 | V |
| Forward Current | IF | 200 | mA |
| LED Configuration | — | 10 Chip Parallel | — |
3.4 Interface Pin Assignment (40-Pin FPC)
The module communicates via a 40-pin FPC connector. The interface is 3-Line / 4-Line SPI. Pin pitch is 0.5mm.
| PIN NO. | Symbol | I/O | Description |
|---|---|---|---|
| 1 | LEDA | P | Power for LED backlight anode |
| 2 | LEDA | P | Power for LED backlight anode |
| 3 | LEDK | P | Power for LED backlight cathode |
| 4 | LEDK | P | Power for LED backlight cathode |
| 5 | GND | P | Ground |
| 6 | GND | P | Ground |
| 7 | GND | P | Ground |
| 8 | GND | P | Ground |
| 9 | GND | P | Ground |
| 10 | GND | P | Ground |
| 11 | NC | — | No connection |
| 12 | NC | — | No connection |
| 13 | NC | — | No connection |
| 14 | NC | — | No connection |
| 15 | NC | — | No connection |
| 16 | NC | — | No connection |
| 17 | NC | — | No connection |
| 18 | NC | — | No connection |
| 19 | NC | — | No connection |
| 20 | NC | — | No connection |
| 21 | NC | — | No connection |
| 22 | NC | — | No connection |
| 23 | VCC | P | Power supply for LCM (2.8V-3.3V) |
| 24 | VCC | P | Power supply for LCM (2.8V-3.3V) |
| 25 | IOVCC | P | I/O power supply (1.8V-3.3V) |
| 26 | IOVCC | P | I/O power supply (1.8V-3.3V) |
| 27 | RESET | I | Reset pin (active low) |
| 28 | TE | O | Tearing effect signal |
| 29 | CSX | I | Chip select pin (low enable) |
| 30 | DCX | I | Command/Data select pin |
| 31 | SCL | I | Serial clock pin |
| 32 | SDA | I/O | Serial data input/output pin |
| 33 | GND | P | Ground |
| 34 | GND | P | Ground |
| 35 | GND | P | Ground |
| 36 | GND | P | Ground |
| 37 | GND | P | Ground |
| 38 | GND | P | Ground |
| 39 | GND | P | Ground |
| 40 | GND | P | Ground |
3.5 Interface Timing Characteristics (3-Line / 4-Line SPI)
Condition: VDDI=1.8V, VDD=2.8V, AGND=DGND=0V, Ta=25°C.
3.5.1 3-Line Serial Interface Timing
| Signal | Symbol | Parameter | MIN | MAX | Unit |
|---|---|---|---|---|---|
| CSX | TCHW | CSX "H" Pulse Width | 15 | — | ns |
| CSX | TCSS | CSX "L" to SCL "H" | 15 | — | ns |
| SCL | TSLW | SCL "L" Pulse Width (Write) | 15 | — | ns |
| SCL | TSHW | SCL "H" Pulse Width (Write) | 15 | — | ns |
| SCL | TSLR | SCL "L" Pulse Width (Read) | 60 | — | ns |
| SCL | TSHR | SCL "H" Pulse Width (Read) | 60 | — | ns |
| SDA | TSDS | Data Setup Time | 10 | — | ns |
| SDA | TSDH | Data Hold Time | 10 | — | ns |
| SDA (DOUT) | TACC | Access Time (Read) | 10 | 50 | ns |
3.6 Mechanical Dimensions
Key mechanical dimensions derived from the outline drawing:
| Item | Specification |
| LCM Outline (H×V) | 74.66 × 74.66 mm (±0.15) |
| LCM Total Thickness | 2.11 ± 0.15 mm |
| LCD & CF Width | 74.26 mm |
| Active Area (AA) Width | 71.86 mm |
| POL Width | 73.76 mm |
| LCD Thickness | 0.8 mm |
| POL Thickness | 0.15 mm |
| FPC + PI Reinforcement Thickness | 0.3 mm |
| FPC Pin Pitch | 0.5 mm (40 pins) |
| General Tolerance | ±0.2 mm |
3.7 Design Notes from Documentation
- Display Type: Main LCD: Transmissive, IPS.
- Main LCD Driver IC: ST7701P.
- Backlight: 10 Chip White LED Parallel configuration.
- Mechanical Design Recommendations:
- Suggested housing visible area (shell opening) should be 0.3mm smaller than the VA (Viewing Area) on each side.
- Suggested housing foam opening should be 0.6mm larger than the VA on each side.
- TP edge must not contact any metal conductor.
- General tolerance for unspecified dimensions: ±0.2mm.
- Tolerance of segments to edge of glass: ±0.2mm.
- RoHS: All materials are ROHS compliant.
4. Application Guidelines & Critical Notes
- Power Supply: The module requires VCC (2.8V typical) and IOVCC (1.8V typical) power supplies. Ensure the power supplies are stable and have low ripple.
- Interface: This module uses 3-Line or 4-Line SPI protocol. The host processor must be configured for the appropriate SPI mode. The DCX pin (Pin 30) is used to select between command and data modes.
- Backlight Driver: A constant current driver is required to supply the backlight via the LEDA (Pins 1, 2) and LEDK (Pins 3, 4). The required driving condition is 200mA total current at 3.0V typical forward voltage (10 Chip Parallel configuration).
- Reset: Ensure the RESET pin (Pin 27) is driven low for a sufficient pulse width to initiate a proper reset before initializing the display.
- Tearing Effect: The TE pin (Pin 28) provides a tearing effect signal to synchronize the MCU to frame memory writing.
- Mechanical Mounting: Follow the mechanical design guidelines for the enclosure and foam opening to ensure proper fit and avoid damage to the glass and FPC.
- Operating Temperature: The module operates from -20°C to +70°C. Satisfactory display performance is only guaranteed within this range.
- Storage: Store the module in a clean environment, free from dust, moisture, and direct sunlight. Storage temperature range is -30°C to +80°C.
- Handling Precautions: Handle the module with care to avoid damage to the glass or FPC. Ground yourself to prevent electrostatic discharge (ESD).
5. Conclusion & Design-In Support
The LS0395I18-R-V1 from Lesson Smart Display Technology is a 3.95-inch IPS TFT-LCD module with a square 480×480 resolution, 16.7M colors, an SPI interface, and a compact mechanical design. It is a reliable display solution suitable for a wide variety of square-format embedded display applications.
For successful design-in, engineers should:
- Obtain and review the complete, official Product Specification (Revision 1.0, dated 2026-05-25) for the full mechanical drawing and the driver IC (ST7701P) datasheet for detailed initialization and timing parameters.
- Design a clean 2.8V power supply for the LCD. Design a backlight constant current driver circuit capable of delivering 200mA at up to 3.3V.
- Configure the host processor's SPI interface to match the timing specifications detailed in this datasheet.
- Follow the mechanical design guidelines for the enclosure and foam opening to ensure proper fit and avoid damage.
- Contact the manufacturer for evaluation modules, sample requests, and further technical support during the design-in phase.
This module is designed to provide a reliable and vibrant display solution for a wide array of applications.
