LSC121I04-L-V1 | 12.1 inch TFT-LCD | 1280x800 (WXGA) | LVDS | With CTP
1. Executive Summary & Product Positioning
The LSC121I04-L-V1 is a 12.1-inch color active matrix TFT LCD module developed by 立信(万安)智慧科技有限公司 (Lesson Smart Display Technology Co., Ltd). This module uses amorphous silicon TFTs as active switching devices. It has a 12.1-inch diagonally measured active area with WXGA resolution (1280 horizontal by 800 vertical pixel array). Each pixel is divided into RED, GREEN, and BLUE dots arranged in a vertical stripe, allowing the module to display 16.7M colors using Hi-FRC technology.
Product Positioning: Designed for the monitoring field, this module combines low power consumption, high transmittance, high contrast ratio, and a wide viewing angle. It features an integrated touch panel and uses a standard LVDS interface. With a typical brightness of 450 cd/m², a contrast ratio of 1200:1, and symmetrical viewing angles (85°/85°/85°/85°), it is an excellent choice for industrial monitors, security systems, medical displays, and other applications where reliability and clear image quality are paramount.
2. Detailed Product Overview & Architecture
The module's architecture is designed for robust performance and straightforward integration. The primary components include:
- TFT-LCD Panel: 12.1-inch diagonal, a-Si TFT active matrix, transmissive, normally black display mode. The resolution is 1280(RGB) × 800 pixels with an active area of 261.12 (H) × 163.20 (V) mm.
- Backlight Unit (B/L): A white LED edge-lit backlight unit that delivers a typical luminance of 450 cd/m². The backlight circuit consists of a specific number of LEDs in series, driven by an external boost circuit on the customer's board. The forward voltage (VF) is 21.6V~26.5V at a forward current (IF) of 240mA. The power consumption of the backlight is 6.14W (Typ).
- Touch Panel (CTP): The module includes an integrated capacitive touch panel. The touch controller IC is a GT911. The touch panel structure is G+G (Glass + Glass). The cover glass has a surface hardness of ≥6H.
- Mechanical Construction: The module outline dimensions are 287.5 (H) × 191.0 (V) × 8.4 (T) mm (Typ, without FPC).
- Interface: The module communicates via a 40-pin connector. The main display interface is LVDS, which uses 4 data pairs and 1 clock pair. The touch panel communicates via a standard I2C interface.
3. Exhaustive Technical Specifications
3.1 General & Mechanical Specifications
| Item | Specification |
| Display Size (Diagonal) | 12.1 inches |
| Resolution (Dots) | 1280(RGB) × 800 (WXGA) |
| Display Technology | a-Si TFT, Transmissive, Normally Black |
| Module Construction | COG+FPC+B/L+CTP |
| Color Depth | 16.7M colors (6-bit + Hi-FRC) |
| Viewing Direction | 85°/85°/85°/85° (U/D/L/R, Typ) |
| Luminance (Brightness, Typ) | 450 cd/m² |
| Contrast Ratio (Typical) | 1200:1 (Typ) |
| Color Gamut | 72% NTSC (Typ) |
| Response Time (Tr+Tf) | 30 msec (Typ) |
| Optical Response Time | 30 msec (Typ) |
| Luminance Uniformity | 80% (Typ) |
| Active Area (H×V) | 261.12 × 163.20 mm |
| Visual Area (H×V) | 261.52 × 163.6 mm |
| Outline Dimension (H×V×D) | 287.5 × 191.0 × 8.4 mm (Typ, without FPC) |
| Pixel Pitch (H×V) | 68 × 204 µm |
| Pixel Arrangement | RGB Vertical Stripe |
| Electrical Interface | LVDS 40-pin |
| Touch Driver IC | GT911 |
| Weight | TBD (grams) |
| RoHS Compliance | Yes |
3.2 Electrical Specifications
3.2.1 Absolute Maximum Ratings (Ta=25°C)
| Parameter | Symbol | Min | Max | Unit |
|---|---|---|---|---|
| LCD Operating Voltage | VDD | 0 | 3.6 | V |
| Operating Temperature | TOP | -20 | +70 | °C |
| Storage Temperature | TST | -30 | +80 | °C |
| Operating Humidity | RH (at 40°C) | -- | 90 | % |
| Storage Humidity | RH (at 40°C) | -- | 90 | % |
3.2.2 DC Specifications (Ta=25°C, VDD=3.3V)
| Parameter | Symbol | Min | Typ | Max | Unit | Remarks |
|---|---|---|---|---|---|---|
| Supply Current | IDD | 150 | 180 | 200 | mA | VDD=3.3V |
| Differential Input High Threshold | VTH | -- | -- | +100 | mV | VIC=1.2V |
| Differential Input Low Threshold | VTL | -100 | -- | -- | mV | VIC=1.2V |
| LVDS Common Mode Voltage | VIC | 0.7 | -- | 1.6 | V | -- |
| LVDS Swing Voltage | VID | ±100 | -- | ±600 | mV | -- |
3.2.3 Backlight Characteristics
Note: The backlight power supply is connected to an external boost driver circuit on the client's board, not using the built-in boost circuit of this TCON.
| Parameter | Symbol | Min | Typ | Max | Unit | Remarks |
|---|---|---|---|---|---|---|
| Forward Voltage | VF | 21.6 | 24 | 26.5 | V | Note 1 |
| Forward Current | IF | -- | 240 | -- | mA | Note 1 |
| Power Consumption | PBL | -- | 6.14 | 6.34 | W | Note 1 |
| BLU On/Off Level (On) | BLU on | 1.9 | -- | -- | V | -- |
| BLU On/Off Level (Off) | BLU off | 0 | -- | 0.8 | V | -- |
| PWM Input (High Level) | PWMIN High | 1.9 | -- | -- | V | -- |
| PWM Input (Low Level) | PWMIN Low | 0 | -- | 0.8 | V | -- |
| PWM Frequency | FPWM | 200 | -- | 20K | Hz | -- |
| PWM Duty Ratio | DPWM | 1 | -- | 100 | % | -- |
| LED Life-Time | -- | 50000 | -- | -- | Hrs | Note 2 |
Note 1: Backlight circuit diagram and drive condition defined with IF=240mA, VF=21.6V~26.4V.
Note 2: LED Life-Time is defined as module brightness decrease to 50% of initial brightness at continuous operating condition of 25±2°C. Life-Time may decrease if IF is larger than 240mA.
3.2.4 AC Specifications (LVDS Input)
| Parameter | Symbol | Min | Typ | Max | Unit | Remarks |
|---|---|---|---|---|---|---|
| LVDS Input Frequency | F | 20 | -- | 85 | MHz | -- |
| LVDS Channel to Channel Skew | TLVSK | -600 | -- | +600 | ps | F=65MHz, VIC=1.2V, VID=±200mV |
3.2.5 Interface Timing Parameters
| Parameter | Symbol | Min | Typ | Max | Unit | Remarks |
|---|---|---|---|---|---|---|
| Frame Rate | -- | 58 | 60 | 62 | Hz | -- |
| Pixels Rate | -- | 66.3 | 72.4 | 78.9 | MHz | -- |
| Horizontal Total Time | tHP | 1380 | 1440 | 1500 | tclk | -- |
| Horizontal Active Time | tHadr | 1280 | 1280 | 1280 | tclk | -- |
| Horizontal Back Porch | tHBP | -- | 78 | -- | tclk | -- |
| Horizontal Front Porch | tHFP | -- | 72 | -- | tclk | -- |
| Vertical Total Time | tVP | 824 | 838 | 872 | tH | -- |
| Vertical Active Time | tVadr | 800 | 800 | 800 | tH | -- |
| Vertical Back Porch | tVBP | -- | 18 | -- | tH | -- |
| Vertical Front Porch | tVFP | -- | 15 | -- | tH | -- |
| Lane | -- | -- | 1 | -- | Lane | LVDS 1-port |
3.2.6 Power Sequence Timing
The specification details a power sequence for the LVDS interface and backlight, with typical timings as follows:
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| T1 (VDD rising to Interface valid) | 0 | -- | 10 | ms |
| T2 (Interface valid to Data valid) | 0 | -- | 50 | ms |
| T3 (Data valid to Backlight On) | 200 | -- | -- | ms |
| T4 (Backlight Off to Data Off) | 200 | -- | -- | ms |
| T5 (Data Off to Interface Off) | 0 | -- | 50 | ms |
| T6 (Interface Off to VDD Off) | 0 | -- | 10 | ms |
| T7 (VDD Off to Next Power On) | 500 | -- | -- | ms |
3.3 LVDS Interface Pin Map (40-Pin Connector)
| Pin No. | Symbol | Function | Pin No. | Symbol | Function |
|---|---|---|---|---|---|
| 1 | NC | No Connection | 21 | NC | No Connection |
| 2 | VDDIN | Power Supply (3.3V) | 22 | GND | Ground |
| 3 | VDDIN | Power Supply (3.3V) | 23 | NC | No Connection |
| 4 | VDDIN | Power Supply (3.3V) | 24 | NC | No Connection |
| 5 | NC | No Connection | 25 | NC | No Connection |
| 6 | GND | Ground | 26 | NC | No Connection |
| 7 | GND | Ground | 27 | NC | No Connection |
| 8 | RIN0- | LVDS Negative Data Signal (-) | 28 | GND | Ground |
| 9 | RIN0+ | LVDS Positive Data Signal (+) | 29 | GND | Ground |
| 10 | GND | Ground | 30 | NC | No Connection |
| 11 | RIN1- | LVDS Negative Data Signal (-) | 31 | NC | No Connection |
| 12 | RIN1+ | LVDS Positive Data Signal (+) | 32 | NC | No Connection |
| 13 | GND | Ground | 33 | NC | No Connection |
| 14 | RIN2- | LVDS Negative Data Signal (-) | 34 | NC | No Connection |
| 15 | RIN2+ | LVDS Positive Data Signal (+) | 35 | NC | No Connection |
| 16 | GND | Ground | 36 | NC | No Connection |
| 17 | LVDS_CLK- | LVDS Negative CLK Signal (-) | 37 | NC | No Connection |
| 18 | LVDS_CLK+ | LVDS Positive CLK Signal (+) | 38 | NC | No Connection |
| 19 | GND | Ground | 39 | VLED / NC | LED Anode / NC |
| 20 | NC | No Connection | 40 | VLED / NC | LED Anode / NC |
Note: The LVDS interface uses 4 data pairs (RIN0, RIN1, RIN2) and 1 clock pair (LVDS_CLK). This is a single-port, 4-lane configuration.
3.4 TP I2C Interface Pin Map
| Pin No. | Symbol | Function |
|---|---|---|
| 1 | RST | Touch Reset |
| 2 | VDD | Touch Power Supply |
| 3 | GND | Ground |
| 4 | INT | Touch Interrupt |
| 5 | SDA | I2C Data |
| 6 | SCL | I2C Clock |
3.5 Optical Specifications
Optical characteristics are measured in a dark room (ambient luminance ≤1 lux) at 25±2°C after 30 minutes of warm-up, using a Luminance meter (Goniometer system and TOPCONE PR730) at a distance of 50cm. The optimum viewing angle direction is 6 o'clock.
| Item | Specification (Typ) |
| White Luminance (Center) | 450 cd/m² |
| Contrast Ratio | 1200:1 |
| Color Gamut | 72% NTSC |
| Viewing Angle (CR>10) | 85°/85°/85°/85° (U/D/L/R) |
| Response Time (Tr+Tf) | 30 msec |
| Luminance Uniformity | 80% |
4. Application Guidelines & Critical Notes
When integrating the LSC121I04-L-V1 module, engineers must adhere to the specific guidelines outlined in the specification to ensure optimal performance and reliability.
- Power Supply (VDD): The module requires a single supply rail of VDD = 3.3V (Typ) for the LCD logic. The absolute maximum rating is 3.6V. The supply current (IDD) is typically 180mA. The power sequence (T1 through T7) must be strictly followed to prevent damage.
- Backlight Driver (External): A critical design note is that the backlight power supply is connected to an external boost driver circuit on the customer's board, and does not use the built-in boost circuit of the TCON. The external LED driver must be designed to provide a constant current of 240mA at a forward voltage of 21.6V to 26.5V. The driver must support PWM dimming via the dedicated PWMIN pin.
- LVDS Interface: This is a standard LVDS interface with 4 data pairs and 1 clock pair. A compatible LVDS transmitter (e.g., SN65LVDT100) should be used. The PCB layout for the LVDS differential pairs must be designed with controlled impedance (100-ohm differential) and matched trace lengths.
- Mechanical Integration: The specification provides detailed mechanical notes. The active area is 261.12(H)×163.20(V) mm. The module dimensions are 287.5(H)×191.0(V)×8.4(T) mm. The tolerance for unspecified dimensions is ±0.2mm. The module construction is G+G with a cover glass hardness of ≥6H.
- Handling Precautions: Do not lose CLK or ENAB signals during operation to avoid damage. Obey the supply voltage sequence. Avoid dew drop atmosphere and do not operate in high temperature/humidity conditions. Do not apply fixed pattern data for a long time to avoid image sticking. Do not disassemble the module.
- Storage: Storage in an electro-conductive polymer packing pouch and under relatively low temperature atmosphere is recommended. Storage conditions are -30°C to +80°C, ≤90% RH at 40°C.
- RoHS Compliance: This module is compliant with the RoHS Directive and uses environmental material.
5. Conclusion & Design-In Support
The LSC121I04-L-V1 from Lesson Smart Display Technology is a robust and feature-rich 12.1-inch WXGA TFT-LCD module. With its high brightness (450 cd/m²), high contrast ratio (1200:1), wide viewing angles, and integrated GT911 touch controller, it is specifically tailored for demanding monitoring and industrial applications. The key design consideration is the external backlight driver requirement.
For design-in support, it is strongly recommended to:
- Obtain and review the full Product Specification (Revision 1.0) for the complete set of LVDS timing diagrams, the detailed mechanical outline drawing, and the CTP specification.
- Design the power supply to provide a stable 3.3V rail for the LCD logic and a capable external constant current backlight driver (240mA at 21.6-26.5V) with PWM control.
- Utilize the mechanical drawing for accurate enclosure design, paying attention to the viewing area, active area, and foam placement.
- Contact the manufacturer for evaluation kits, sample requests, and technical support during the design-in phase.
This module is engineered to deliver consistent, reliable, and visually clear display performance for professional monitoring and industrial applications.
