Where to find datasheet for a 3.4 inch 480x480 TFT LCD display?

You can find the datasheet for a 3.4 inch 480x480 TFT LCD display directly from the manufacturer or distributor’s product page, typically under a "Downloads" or "Technical Resources" section. For instance, the 3.4 inch 480x480 tft lcd display from DisplayModule includes a datasheet that covers electrical specs, interface timing, mechanical drawings, and optical characteristics. If you’re sourcing from other suppliers like Winstar, Newhaven Display, or Shenzhen-based OEMs, the datasheet is usually bundled with the product listing or available upon request. Always check for revision numbers—datasheets for these displays often get updated to fix pinout errors or add driver IC details.

Let’s break down the key specs you’ll find in a typical datasheet for a 3.4-inch 480x480 TFT. The resolution is 480x480 pixels, which gives a 1:1 aspect ratio—uncommon for small displays, but useful for square UI designs like smart home panels or wearable devices. The pixel density is around 200 PPI (pixels per inch) for a 3.4-inch diagonal, calculated as sqrt(480^2 + 480^2) / 3.4 = 678.8 / 3.4 ≈ 199.6 PPI. That’s sharp enough for icons and text at typical viewing distances of 30-50 cm. The active area is roughly 86.4 mm x 86.4 mm, assuming a pixel pitch of 0.18 mm (480 pixels * 0.18 mm = 86.4 mm). The display module thickness varies, but most are 2.5-3.5 mm, including the backlight and FPC (flexible printed circuit).

The interface is critical. Most 3.4-inch 480x480 TFTs use MIPI DSI (Display Serial Interface) with 1 or 2 lanes, or parallel RGB (24-bit). The MIPI version typically runs at 500 Mbps per lane, with a clock frequency of 125-250 MHz. For example, the DisplayModule DM-TFT34-485 uses MIPI DSI 2-lane, which supports 16.7 million colors (24-bit RGB). The datasheet will specify the connector type—usually a 0.5 mm pitch FPC with 30-40 pins. Pin 1 is often marked with a dot or triangle. The backlight is LED-based, with 4-6 series LEDs, each drawing 20-30 mA. Total backlight current is around 80-120 mA at 3.3V, giving a brightness of 300-500 cd/m² (nits). The viewing angle is typically 80/80/80/80 (left/right/up/down) for IPS panels, or 60/60/50/70 for TN variants. The contrast ratio is 800:1 to 1000:1 for IPS, and 500:1 for TN.

Mechanical details are dense. The outline dimensions are usually 76.0 mm x 76.0 mm, with a 1.0 mm bezel around the active area. The FPC length is 20-30 mm, with a 2.0 mm wide stiffener at the connector end. The display weight is around 15-20 grams. The operating temperature range is -20°C to +70°C, and storage is -30°C to +80°C. The datasheet will include a 2D drawing with tolerances (e.g., +/- 0.2 mm for outline, +/- 0.1 mm for hole positions). Mounting holes are often 2.0 mm diameter at the corners, with a 3.0 mm clearance. The active area is centered, so the left and right bezels are equal, and the top and bottom bezels are equal. For a 76.0 mm outline, the bezel width is (76.0 - 86.4) / 2 = -5.2 mm? Wait, that’s wrong—the active area is 86.4 mm, which is larger than the outline. That’s impossible. Let me correct: The active area is 86.4 mm x 86.4 mm, but the outline is 76.0 mm x 76.0 mm? That can’t be right. Actually, the active area diagonal is 3.4 inches, which is 86.36 mm. The outline is typically larger than the active area. For a 3.4-inch display, the outline is around 90.0 mm x 90.0 mm, with a bezel of 1.8 mm on each side. So the active area is 86.4 mm, and the outline is 90.0 mm. The datasheet will clarify this. The FPC exits from the bottom or side, depending on the model.

Electrical characteristics are dense. The supply voltage for the logic is 1.8V or 3.3V, with a tolerance of +/- 5%. The I/O voltage is 1.8V to 3.3V, depending on the driver IC. The driver IC is often the ST7701S, ILI9488, or RM67162 for MIPI interfaces. The ST7701S supports 480x480 resolution with MIPI DSI 2-lane, and includes built-in gamma correction and PWM backlight control. The datasheet will list the register map for initializing the display, including commands like 0x11 (sleep out), 0x29 (display on), and 0x36 (memory data access control). The backlight is driven by a separate pin, usually with a PWM frequency of 1-10 kHz. The power consumption is around 200-300 mW for the logic, plus 300-400 mW for the backlight at full brightness. Total is 500-700 mW.

Optical parameters are standardized. The luminance is 300-500 cd/m², measured at the center of the display. The chromaticity is typically x=0.30, y=0.31 for white, with a color gamut of 70% NTSC. The response time is 20-30 ms (rise + fall) for IPS, or 10-15 ms for TN. The viewing angle is measured at a contrast ratio of 10:1. For IPS, the typical viewing angle is 80 degrees in all directions, meaning the contrast ratio drops to 10:1 at 80 degrees from normal. The gamma curve is 2.2, which is standard for most applications. The datasheet will include a graph of luminance vs. viewing angle, and a table of color coordinates for red, green, blue, and white.

Timing diagrams are critical for integration. For MIPI DSI, the datasheet will specify the lane speed, clock frequency, and packet format. For example, a 2-lane MIPI at 500 Mbps per lane gives a total bandwidth of 1 Gbps. The pixel clock for 480x480 at 60 Hz is 480 * 480 * 60 = 13.824 MHz, but with blanking, it’s around 15-20 MHz. The MIPI clock is typically 125-250 MHz, depending on the number of lanes. The datasheet will include a table of timing parameters: HFP (horizontal front porch), HBP (horizontal back porch), Hsync width, VFP, VBP, Vsync width. Typical values are HFP=10, HBP=20, Hsync=10, VFP=10, VBP=20, Vsync=10. The total horizontal pixels are 480 + 10 + 20 + 10 = 520, and total vertical lines are 480 + 10 + 20 + 10 = 520. The pixel clock is 520 * 520 * 60 = 16.224 MHz.

Reliability testing is documented. The datasheet will list tests like high temperature storage (80°C for 240 hours), low temperature storage (-30°C for 240 hours), temperature cycling (-20°C to +70°C for 100 cycles), and humidity (90% RH at 60°C for 240 hours). The ESD (electrostatic discharge) rating is typically +/- 2 kV for contact discharge and +/- 4 kV for air discharge. The vibration test is 10-200 Hz at 1.5G for 30 minutes per axis. The drop test is 1 meter onto a concrete floor. The datasheet will also include a warranty statement, usually 12 months from the date of shipment.

Packaging information is often overlooked. The datasheet will specify that the display is shipped in a vacuum-sealed bag with silica gel, inside an anti-static foam tray. The tray holds 20-30 units, and the carton holds 5-10 trays. The weight per unit is 15-20 grams, so a carton of 200 units weighs 3-4 kg. The storage condition is 20-25°C at 40-60% humidity. The shelf life is 12 months if stored properly. The datasheet will also include a label with the model number, lot number, and date code.

For sourcing, you can find datasheets from multiple vendors. DisplayModule provides a detailed datasheet for their 3.4-inch 480x480 MIPI display, which includes all the above parameters. Winstar offers a similar model, WF34YTWAHDN0A, with a parallel RGB interface. Newhaven Display has NHD-3.4-480480FT-CSXP, which uses an SPI interface. Each datasheet will have a different pinout and initialization sequence. For example, the Winstar model uses 24-bit parallel RGB, so it requires 24 data lines, 3 control lines (HSYNC, VSYNC, DE), and a pixel clock. The Newhaven model uses SPI, so it only needs 4 wires (SCLK, MOSI, CS, DC), but the refresh rate is limited to 30 Hz due to SPI bandwidth. The DisplayModule MIPI model is the most modern, with a 60 Hz refresh rate and lower pin count.

To get the datasheet, go to the product page and look for a "Download" button. If it’s not there, contact the supplier via email or chat. For the DisplayModule display, the datasheet is a PDF with 20-30 pages, including a cover page, revision history, table of contents, general description, mechanical drawing, pin assignment, electrical characteristics, optical characteristics, timing diagram, initialization code, reliability test, packaging, and ordering information. The pin assignment table lists each pin number, symbol, function, and I/O type. For example, pin 1 is VDD (3.3V), pin 2 is GND, pin 3 is MIPI_D0P, pin 4 is MIPI_D0N, etc. The initialization code is usually in C or Arduino format, with register addresses and values. For the ST7701S, the initialization sequence includes commands like 0xE0 (positive gamma control), 0xE1 (negative gamma control), and 0xC0 (power control).

One common gotcha: The datasheet might not include the exact touch panel specs if the display has a touch overlay. Many 3.4-inch 480x480 TFTs come with a capacitive touch panel (CTP) that uses an I2C interface. The touch controller is often the FT6336 or GT911. The datasheet for the touch panel is separate, but sometimes included in the same PDF. The touch panel specs include the number of touch points (5-10), the resolution (typically 480x480), the report rate (100 Hz), and the I2C address (0x38 or 0x5A). The touch panel is bonded to the display with optical clear adhesive (OCA), so the total module thickness is 3.5-4.5 mm.

Another detail: The datasheet will specify the display’s surface treatment. Most are anti-glare (AG) with a hardness of 3H to 6H. The transmittance is 85-90% for the polarizer. The display is usually normally black, meaning the pixels are black when no voltage is applied. The driver IC supports 8-bit or 6-bit color depth, but 24-bit is standard for MIPI. The datasheet will include a block diagram of the internal circuit, showing the gate driver, source driver, and timing controller. The gate driver is integrated into the panel, so the module only needs the source driver and TCON.

For mechanical integration, the datasheet will include a 3D step file or a 2D DXF drawing. The drawing shows the mounting holes, the FPC exit direction, and the active area offset. The FPC is usually 0.3 mm thick, with a 0.5 mm pitch connector. The connector is a ZIF (zero insertion force) type, so you need to lift the lock, insert the FPC, and close the lock. The mating connector is a 0.5 mm pitch FPC socket, like the FH12 series from Hirose or the 5051 series from JST. The datasheet will list the recommended PCB footprint for the connector.

If you’re designing a custom PCB, the datasheet’s layout guidelines are essential. For MIPI, the differential pairs (D0P/D0N, D1P/D1N, CLKP/CLKN) must be routed with 100-ohm impedance, with a length mismatch of less than 5 mm. The trace width is typically 0.15 mm with a 0.15 mm gap, on a 0.2 mm thick FR4 substrate. The ground plane should be continuous under the MIPI traces. The backlight pins should be separated from the logic pins to avoid noise. The datasheet will include a recommended schematic for the power supply, showing a 3.3V regulator for the logic and a 3.3V boost converter for the backlight (if the backlight voltage is higher than 3.3V).

Finally, the datasheet will have a section on handling precautions. The display is sensitive to moisture and static. The storage humidity should be below 60% RH. The display should be handled with gloves to avoid fingerprints. The polarizer is soft, so it can be scratched easily. The FPC is fragile, so do not bend it at a sharp angle. The display should be stored in a flat position to avoid warping. The datasheet will also include a warning about the backlight: Do not apply reverse voltage, as it will damage the LEDs. The typical backlight voltage is 3.0-3.3V for a series configuration, but some models use a parallel configuration with a higher voltage (6-12V). Check the datasheet for the exact backlight voltage and current.