Specifications
| Diagonal size | 3.5" |
|---|---|
| Resolution | 320×480 |
| Panel type | IPS |
| Interface | SPI / MCU (8080 parallel) |
| Touch | Resistive (RTP) |
| Brightness | 350 cd/m² (nits) |
| Colors | 65K |
| Operating temp. | -20 to +70 °C |
| FPC / connector | 40-pin |
| Supply voltage | 3.3V |
Engineering notes
Why ST7796S instead of ILI9488
| ST7796S | ILI9488 |
|---|---|---|
SPI pixel format | 16-bit | 18-bit only |
Bytes per full frame | 307,200 | 460,800 |
Theoretical fps @40 MHz SPI | ~16 | ~11 |
For SPI designs this is the module we recommend. See the ILI9488 notes for background.
Resistive touch
Resistive touch works with gloves, styluses and wet fingers, and it costs less than capacitive. It needs a one-time calibration (store the coefficients in flash) and supports a single touch point.
Typical uses
3D printer and CNC controllers, handheld test equipment, industrial keypads and battery-powered instruments.
Related: 3.5 inch displays.
Integration calculations
Figures below are calculated from the DE-350-SPI-RTP’s 320×480 resolution and SPI / MCU (8080 parallel), so you can size the host before requesting samples. Refresh rates are theoretical bus limits; real throughput is lower once command overhead and rendering time are included.
| Pixel density | 165 PPI |
|---|---|
| Native orientation | Portrait (320×480); rotate in the driver for landscape UIs |
| Full frame buffer | 300 KB at RGB565 · 450 KB at RGB888 |
| SPI full-frame refresh (RGB565, theoretical) | 16 fps at 40 MHz · 33 fps at 80 MHz |
| 8080 parallel refresh (theoretical, 10 MHz WR) | 65 fps on a 16-bit bus · 33 fps on an 8-bit bus |
At 350 cd/m² it is sized for indoor use; the backlight can be upgraded for brighter environments.
Hosts with a native SPI / MCU (8080 parallel) peripheral
SPI up to 80 MHz; the 300 KB RGB565 frame fits in internal SRAM.
- STM32, RP2040, nRF52
Any MCU with an SPI peripheral and DMA; partial-buffer rendering keeps RAM use low.
LCD_CAM peripheral drives 8/16-bit 8080 (i80) panels with DMA.
- STM32 with FSMC/FMC
The external memory controller maps the panel as memory for fast writes.
Interface support is based on each processor’s published display peripherals, not a bench test of this module. Ask us for tested init code.
Alternatives in the catalog
Other 3.5" options
- PJT350P15H50-400P54C3.5" 320×240 · RGB (parallel) · TN · 400 nits
- PJ3502B01-32H54P4003.5" 320×240 · RGB (parallel) · IPS · 400 nits
- PJT350P15H32-400P54N3.5" 320×240 · RGB (parallel) · TN · 400 nits
- PJ3501I01-34H54P3003.5" 320×240 · RGB (parallel) · IPS · 300 nits
- PJ3501I12-22H16P2503.5" 320×480 · SPI · TN · 250 nits
- PJ3506G01-31H30P200C3.5" 480×640 · MIPI DSI · TN · 200 nits
Frequently asked questions
Is ST7796S code compatible with ILI9488?
The command sets are similar but the init sequences and SPI pixel formats differ. Use an ST7796S-specific driver; TFT_eSPI, LovyanGFX and LVGL all include one.
Can I get a capacitive touch version?
Yes, capacitive touch versions are available as an option. Ask an engineer for the current part number.
How do I calibrate resistive touch?
Run a three- or five-point calibration once, store the coefficients in non-volatile memory, and apply them in your touch driver.
What is the brightness of the DE-350-SPI-RTP?
350 cd/m² typical with the standard backlight. At 350 cd/m² it is sized for indoor use; the backlight can be upgraded for brighter environments.
What interface does the DE-350-SPI-RTP use?
SPI / MCU through a 40-pin FPC. Pin definition and timing are in the datasheet, which you can request on this page.
Which processors can drive the DE-350-SPI-RTP?
ESP32 / ESP32-S3: SPI up to 80 MHz; the 300 KB RGB565 frame fits in internal SRAM. STM32, RP2040, nRF52: Any MCU with an SPI peripheral and DMA; partial-buffer rendering keeps RAM use low. ESP32-S3: LCD_CAM peripheral drives 8/16-bit 8080 (i80) panels with DMA. STM32 with FSMC/FMC: The external memory controller maps the panel as memory for fast writes.
Does the DE-350-SPI-RTP have a touch panel?
Yes, a resistive (RTP) touch panel. The non-touch version and other cover-glass options can be built.
What is the MOQ and lead time for the DE-350-SPI-RTP?
Samples start from 1 pc. Production MOQ and lead time depend on quantity and any customization (FPC length, backlight, touch), and are agreed per project with our sales team. Send your annual volume and target date for a quote.
