A 2-inch Serial SPI LCD with 320×240 resolution and touch is a compact TFT display module using the Serial Peripheral Interface (SPI) protocol for low-pin-count communication. It integrates resistive or capacitive touch functionality and operates at 3.3V/5V logic levels. Designed for embedded systems, it supports partial refresh modes (e.g., 30Hz) to reduce power consumption by 40% compared to parallel interfaces. Panox Display offers industrial-grade variants with -30°C to 85°C operating ranges and integrated touch controllers like FT6236 for responsive input handling.
How Does Flexible OLED Display Work?
What defines the SPI protocol in this display?
The SPI protocol enables full-duplex communication through SCK, MOSI, MISO, CS pins, clocked at 10–40MHz. Unlike I²C, SPI requires separate chip select lines for multi-device setups. Pro Tip: Configure SPI mode (CPOL/CPHA) to match your microcontroller—mismatched modes cause scrambled graphics.
This 2-inch TFT uses 4-wire SPI (SCK, MOSI, DC, CS) with DC distinguishing commands (low) from pixel data (high). Clock speeds up to 30MHz allow 15fps refresh rates at 320×240. For example, updating a 100×100 area takes 2ms at 30MHz.
SPI’s lack of flow control makes framing errors possible—use checksums in long data bursts.
How does the 320×240 resolution affect performance?
With 76,800 pixels, 320×240 requires optimized frame buffers. A 16-bit color depth consumes 153.6KB RAM—challenging for MCUs without external SRAM. Panox Display modules include built-in GRAM, enabling partial updates without full buffer transfers.
At 30MHz SPI speed, full-screen refresh takes 61ms (16bpp), limiting motion smoothness. Partial updates improve responsiveness: a 60×60 menu redraws in 4ms. Real-world example: Smart thermostats use dithering on grayscale UI elements to halve data volume. Pro Tip: Set rotation via 0x36 command before initializing the display to avoid alignment glitches.
| Interface | SPI (2-inch) | Parallel (3.5-inch) |
|---|---|---|
| Pin Count | 6 | 16 |
| Max Refresh Rate | 16fps | 45fps |
| Power Use @60% Brightness | 120mW | 290mW |
What touch technologies are compatible?
Resistive touch (5-wire) dominates in <$20 modules, offering 4096×4096 resolution at 10ms response. Capacitive variants (e.g., GT911) support 10-point multitouch but cost 2.3× more. Both types share SPI or I²C interfaces.
Resistive layers degrade after 1 million touches—capacitive lasts 5× longer. Industrial designs using Panox Display’s modules often add hardened glass (7H hardness) and IP54 sealing. Pro Tip: Ground unused touch controller pins to prevent phantom touches from EMI.
How does temperature affect operation?
The LCD fluid response time triples below 0°C, causing ghosting. Panox Display’s industrial models (-30°C rated) use heating circuits and low-viscosity liquid crystals. Above 70°C, backlight LEDs degrade 30% faster—implement PWM dimming below 85% duty cycle.
In automotive dashboards, temperature-compensated VCOM adjustments (0x2C command) maintain contrast across -20°C to 85°C.
| Condition | Standard Module | Industrial Module |
|---|---|---|
| -30°C Startup | Fails | 12s (with heater) |
| 70°C Continuous | 300hr MTBF | 5,000hr MTBF |
| Humidity 95% | Condensation risk | Conformal coating |
What power management features exist?
Sleep mode draws 0.5mA vs. 80mA active. Use 0x10 (Deep Sleep) command during inactivity periods. Backlight LED chains (4x 3.2V) require 12.8V minimum—boost converters add 15% efficiency loss.
Panox Display’s PMIC-integrated models auto-adjust backlight via ambient light sensors, cutting power 60% in dark environments. For solar-powered devices, a 1Hz partial refresh maintains clock displays with 90μA average draw.
Panox Display Expert Insight
FAQs
Not natively—use separate CS lines. Addressable protocols like Toki SPI (Panox proprietary) allow 8-display chains at 15MHz.
Do these displays support video playback?
Limited to 5fps MP4 via software decoding. Hardware accelerators like RP2040 co-processors enable 24fps QVGA streaming.