LS0200I05-SP-V1: 1.99-Inch a-Si TFT LCD Module, 400×454 Resolution, 16.7M Colors, SPI Interface

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Product Subtitle / Keywords:
1.99 Inch Display, 400(RGB)×454 Resolution, Transmissive a-Si TFT-LCD, SPI Interface, COG+FPC+B/L, 16.7M Colors, 35.82×42.48×1.6 mm, 900:1 Contrast Ratio, 25ms Response Time, 250 cd/m² Luminance, 80° Viewing Angle, -20°C~60°C Operating Temperature

1. Executive Summary & Product Positioning

The LS0200I05-SP-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 1.99-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 SPI (Serial Peripheral Interface) pinout and timing, and comprehensive electro-optical performance. It delivers a resolution of 400(RGB)×454 with 16.7M-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).
  • 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.
  • Panel Size: 1.99 inch.
  • Resolution: 400(RGB)*454.
  • Display Colors: Up to 16.7M colors.
  • 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) 35.82 × 42.48 × 1.6 mm
Number of dots 400(RGB) × 454 pixel
Active area (H×V) 33.42 × 37.93 mm

3.2 Electrical & Interface Specifications

3.2.1 Absolute Maximum Ratings

Parameter Symbol Min Max Unit
Supply voltage for logic IOVCC -0.3 +3.3 V
Input voltage for analog circuit VCC -0.3 +3.3 V
Operating temperature TOP -20 60 °C
Storage temperature TST -30 70 °C
Humidity RH - 90% (55°C) RH

3.2.2 Electrical Characteristics (DC – Recommended Operating Conditions)

Parameter Symbol Min Typ Max Unit
Analog operating voltage VCC 2.5 2.8 3.3 V
Logic operating voltage IOVCC 1.65 1.8 3.3 V
Input voltage “H” level VIH 0.8 IOVCC - IOVCC V
Input voltage “L” level VIL GND - 0.2 IOVCC V
Output voltage “H” level VOH 0.9 IOVCC - IOVCC V
Output voltage “L” level VOL GND - 0.2 IOVCC V

3.2.3 Backlight Characteristics

Item Symbol Min Typ Max Unit Condition
Forward voltage Vf 2.8 3.0 3.4 V If=60mA, Ta=25°C
Number of LED - 3 3 3 Piece -
Connection mode S/P 3Parallel 3Parallel 3Parallel - -

3.2.4 Pin Description (24-pin FPC)

Pin No Symbol Description
1 TP VDD2V8 Power supply (2.8)
2 TP_INT Interrupt request to the host, or Wakeup request from the host.
3 TP_SDA I2C Data Input & Output
4 TP_SCL I2C Clock Input
5 TP_RSTN Reset signal for TP
6 GND System Ground
7 VDD(2.8V) I/O Power supply (2.8V)
8 LED_A Backlight LED Anode.
9 LED_K Backlight LED Cathode.
10 NC NC
11 NC NC
12 GND System Ground
13 VDDIO_1.8V I/O Power supply (1.8)
14 VDDIO_1.8V I/O Power supply (1.8)
15 GND System Ground
16 LCD_RST_N Reset Signal pin (“Low” is enable)
17 SPI-CS Chip selection pin (“Low” is enable)
18 SPI-SCL SCL Signal
19 SPI-DCX Display data/command selection pin (RS=1 display data or parameter, RS=0 command data)
20 SPI-SDA Serial data input/output pin
21 TE Tearing effect output pin to synchronize
22 GND System Ground
23 GND System Ground
24 NC NC

Interface Summary:

  • SPI Interface: Uses SPI-SCL (Serial Clock), SPI-SDA (Serial Data), SPI-DCX (Data/Command), SPI-CS (Chip Select), and LCD_RST_N (Reset) for communication.
  • TE Pin (Pin 21): Tearing effect output — can be used for frame synchronization.
  • Backlight: Dedicated LED_A (Anode, Pin 8) and LED_K (Cathode, Pin 9) pins.
  • Power: VDD(2.8V) (Pin 7) for main logic, VDDIO_1.8V (Pins 13, 14) for I/O interface, GND (Pins 6, 12, 15, 22, 23) for ground.
  • Touch Panel Interface: Pins 1-5 provide a dedicated interface for an external capacitive touch panel (TP VDD2V8, TP_INT, TP_SDA, TP_SCL, TP_RSTN).

3.2.5 Reset Timing

Parameter Symbol Min. Typ. Max. Unit Test Condition
Reset “Low” level width tRW1 1 - - ms Power On
Reset “Low” level width tRW2 500 - - us Operation
Reset time tRT - - 20 ms -

Reset Timing Notes (from document):

  • Power On Reset: The RESET_N pin must be held low for at least 1ms after power supplies (VDDIO, VCIO, VCI) are stable.
  • Operation Reset: During normal operation, the RESET_N pin must be held low for at least 500μs to initiate a reset.
  • Reset Time: After releasing the reset pin, the device requires 20ms to complete the initialization sequence.
  • Spike Rejection: A reset pulse shorter than 5μs will be rejected.

3.2.6 Power On/Off Sequence

The document provides a Power On/Off Sequence diagram with the following key timing requirements:

  • Power On Sequence:

    1. Apply VDDIO.
    2. After >1ms, apply VCI.
    3. After >1ms, release RESX (set to high).
    4. After 210μs, send initialization commands.
    5. After 120ms, send Sleep Out command.
    6. After 120ms, send Display On command.

  • Power Off Sequence:

    1. Send Display Off command.
    2. Send Sleep In command.
    3. Wait 120ms.
    4. Set RESX low.
    5. Remove VCI.
    6. After >1ms, remove VDDIO.

3.3 Optical & Electro-Optical Characteristics (Ta=25°C)

Item Symbol Condition Min. Typ. Max. Unit Remark
Response time Tr+Tf Θ=0° - 25 - ms Note 1
Contrast ratio Cr Θ=0° 800 900 - - Note 2
Color gamut S(%) Θ=0° 64 67 - % -
Luminance uniformity δWHITE Θ=0° 75 - - % Note 3
Viewing angle range Θx+ CR≥10 - 80 - deg Note 4
Viewing angle range Θx- CR≥10 - 80 - deg Note 4
Viewing angle range Θy+ CR≥10 - 80 - deg Note 4
Viewing angle range Θy- CR≥10 - 80 - deg Note 4
LCM Luminance Lv Θ=0° 200 250 - Cd/m² Note 5
CIE (X,Y) Chromaticity White(X) Θ=0° - TBD - - Note 6
CIE (X,Y) Chromaticity White(Y) Θ=0° - TBD - - Note 6

Notes (from document):

Note 1: Definition of Response Time
Response time is the time required for the display to transition from White to black (Rise Time, Tr) and from black to white (Decay Time, Tf). Tr refers to the time needed to switch from a black screen to a white screen, and Tf refers to the time needed to switch from a white screen to a black screen.

Note 2: Definition of Contrast Ratio
Contrast Ratio (CR) is defined mathematically by the following formula:
Contrast Ratio = Average Surface Luminance with all white pixels / Average Surface Luminance with all black pixels

Note 3: Definition of Luminance Uniformity
The uniformity in surface luminance (WHITE) is determined by measuring luminance at each test position, and then dividing the minimum luminance of all white pixels by the maximum luminance of all white pixels.
WHITE = Minimum Surface Luminance with all white pixels / Maximum Surface Luminance with all white pixels

Note 4: Definition of Viewing Angle
Viewing angle is the angle at which contrast ratio is greater than a specific value. For TFT module, the specific value of contrast ratio is 10. The 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 5: Definition of Surface Luminance
Surface luminance is the LCD surface luminance with all white pixels.
Lv = Average Surface Luminance with all white pixels

Note 6: Definition of Chromaticity
CIE (X,Y) chromaticity is the Center point value.

Note 7: Measurement Instruments
For Viewing angle and response time testing, the testing data is based on Autronic-Melchers’s ConScope series instruments. For contrast ratio, Surface Luminance, Luminance uniformity and CIE, the testing data is based on CS-2000 (BM-7/CA310) photo detector.

3.4 Version Record

Version Revise Date Page Content
00 — ALL New released

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, high-resolution display with excellent viewing angles

Critical Design Considerations

  1. Interface (SPI): This module uses an SPI (Serial Peripheral Interface) for communication. The host MCU must have at least 5 GPIOs (SPI-SCL, SPI-SDA, SPI-DCX, SPI-CS, LCD_RST_N) to drive the display.

  2. Power Supply:

    • Provide stable VCC (2.5V to 3.3V, 2.8V typical) for the analog circuit.
    • Provide stable IOVCC (1.65V to 3.3V, 1.8V typical) for the logic circuit.
    • The backlight requires a constant-current LED driver connected to LED_A (Anode, Pin 8) and LED_K (Cathode, Pin 9), set to 60 mA at approximately 3.0V (Typ).

  3. Touch Panel Interface:

    • The module includes a dedicated TP interface (Pins 1-5) for an external capacitive touch panel.
    • The TP interface uses: TP_SCL (I²C clock), TP_SDA (I²C data), TP_RSTN (Reset), TP_INT (Interrupt), and TP VDD2V8 (Power).
    • Ensure the touch panel controller is properly initialized via its I²C interface.

  4. Reset Circuit:

    • The LCD_RST_N pin (Pin 16) is active low.
    • Power On Reset: It must be driven low for at least 1ms after power supplies are stable.
    • Operation Reset: It must be driven low for at least 500μs during normal operation.
    • After releasing RESET, wait 20ms before sending any commands.
    • A pulse shorter than 5μs will be rejected.

  5. Power On/Off Sequence:

    • Power On: VDDIO → VCI → RESX → Commands → Sleep Out → Display On.
    • Power Off: Display Off → Sleep In → RESX → VCI → VDDIO.
    • Strictly follow the timing requirements to prevent damage to the module.

  6. TE (Tearing Effect) Pin (Pin 21):

    • The TE pin outputs the display’s tearing effect signal.
    • This signal can be used to synchronize MCU frame writes with the display’s internal refresh cycle, preventing screen tearing.
    • If not used, leave this pin open.

  7. Mechanical Integration:

    • Module Outline: 35.82mm (H) × 42.48mm (V) × 1.6mm (D).
    • Active Area: 33.42mm × 37.93mm.
    • FPC: The module uses a 24-pin FPC.

  8. Viewing Angle Characteristics:
    This module provides excellent viewing angle performance (CR ≥ 10):

    • Top (12 o'clock): 80° (Typ)
    • Bottom (6 o'clock): 80° (Typ)
    • Left (9 o'clock): 80° (Typ)
    • Right (3 o'clock): 80° (Typ)

    The module provides near-perfect viewing angles in all directions, making it ideal for wearable devices.

  9. Optical Performance:

    • Response Time: 25ms (Typ) – fast enough for most GUI applications.
    • Contrast Ratio: 800 (Min), 900 (Typ) – excellent contrast performance.
    • Color Gamut: 64% (Min), 67% (Typ).
    • Luminance Uniformity: 75% (Min).
    • Luminance (IF = 60mA): 200 cd/m² (Min), 250 cd/m² (Typ).

  10. Temperature Limits:

    • Operating Temperature: -20°C to +60°C.
    • Storage Temperature: -30°C to +70°C.

Handling & Compliance

  • Observe standard ESD precautions during handling and assembly.
  • The module contains fragile glass and a 24-pin FPC – handle with care.
  • Avoid bending the FPC sharply, especially near the connector interface.
  • The module has a total thickness of 1.6mm – be careful when handling to avoid flexing.

5. Conclusion & Design-In Support

The LS0200I05-SP-V1 specification details a high-performance 1.99-inch display module with an SPI interface — an excellent choice for wearable and compact display applications requiring high resolution, excellent image quality, and wide viewing angles.

Key Strengths:

  1. High Resolution: The 400×454 resolution in a 1.99-inch format provides excellent pixel density for sharp text and graphics.

  2. High Color Depth: 16.7M colors (24-bit true color) provides excellent color reproduction.

  3. Excellent Viewing Angles: 80° viewing angles in all directions ensure consistent image quality from any perspective.

  4. Integrated Touch Panel Interface: The dedicated TP interface (Pins 1-5) simplifies integration with external capacitive touch panels.

  5. Excellent Contrast Ratio: 900:1 (Typ) provides outstanding image quality.

  6. Fast Response Time: 25ms (Typ) – suitable for most GUI applications.

  7. TE (Tearing Effect) Support: The dedicated TE pin enables tear-free graphics synchronization.

  8. Comprehensive Power Sequencing Documentation: Detailed power on/off sequence timing ensures reliable operation.

Main Design Focus:

  • The critical design task is properly implementing the SPI interface and strictly following the power on/off sequence to ensure reliable operation.
  • Supporting requirements:
    • Provide stable VCC (2.8V typical) and IOVCC (1.8V typical) power.
    • Provide a constant-current backlight driver set to 60 mA at 3.0V (Typ).
    • Mechanical integration — the module outline is 35.82mm × 42.48mm × 1.6mm.
    • FPC connector — verify the 24-pin FPC.
    • Touch panel integration — connect and initialize the external touch panel via the dedicated TP interface.
    • Reset timing — ensure proper reset pulse width (≥1ms for power on, ≥500μs for operation) and wait times (20ms after reset).
    • Power sequencing — strictly follow the VDDIO → VCI → RESX sequence for power on and the reverse for power off.

This module is an excellent choice for high-end wearable devices, smartwatches, and any compact IoT application requiring a high-resolution display with excellent viewing angles and integrated touch panel support.