What is the resolution of a 3.2 inch 240x320 TFT display?

The resolution of a 3.2 inch 240x320 TFT display is exactly what the numbers say: 240 pixels in width and 320 pixels in height, which gives you a total of 76,800 pixels. That's not a lot by today's standards where phones pack millions of pixels, but for a small screen like this it's actually quite practical. The pixel density comes out to about 125 pixels per inch (PPI) based on the diagonal size and resolution. Let's break down what that means in real-world terms: at 125 PPI, individual pixels are visible if you hold the screen close to your face, but from a typical viewing distance of 12 to 18 inches, the display looks reasonably sharp for text, icons, and basic graphics. This resolution is classified as QVGA (Quarter Video Graphics Array), which was a common standard for early smartphones, feature phones, and portable gadgets. The 3.2 inch size combined with 240x320 means the aspect ratio is 3:4, which is portrait-oriented by default, but you can rotate the content in software depending on your application. The 3.2 inch 240x320 tft display module uses an SPI interface, which is a serial communication protocol that requires only a few pins to drive the screen, making it ideal for microcontrollers like Arduino, ESP32, STM32, and Raspberry Pi Pico. The SPI clock speed typically ranges from 10 MHz to 40 MHz, and at 20 MHz, you can refresh the entire 240x320 frame in about 12 milliseconds, which translates to roughly 83 frames per second, though the actual refresh rate is limited by the display controller, often around 60 Hz. The display controller inside these modules is usually an ILI9341 or a compatible variant, which supports 16-bit color depth (65,536 colors) or 18-bit color depth (262,144 colors) depending on how you wire it. The ILI9341 can handle a maximum resolution of 240x320 natively, so there's no scaling or interpolation happening. The pixel pitch, which is the distance between the centers of two adjacent pixels, is approximately 0.2025 mm for both the horizontal and vertical directions. That means each pixel is about 0.2 mm wide, which is small enough to render smooth curves and fine text when viewed at arm's length. The active area of the display measures about 48.6 mm in width and 64.8 mm in height, which gives you a diagonal of roughly 81.28 mm, or 3.2 inches. The bezel around the active area adds a few millimeters, typically 2 to 3 mm on each side, so the total module size is around 54 mm by 76 mm. The thickness of the module including the PCB and the LCD glass is usually between 3.5 mm and 5 mm, depending on whether it has a backlight diffuser or a touch panel overlay. The backlight is typically driven by 4 to 6 white LEDs in series, requiring a voltage of around 3.0 to 3.3 volts and a current of about 20 to 30 mA per LED, so the total backlight power consumption is around 100 to 200 mW. Without the backlight, the LCD itself consumes very little power, typically under 10 mW at full brightness, because TFT pixels are passive and only draw power when switching states. The contrast ratio is usually around 500:1 to 1000:1 for these small TFT panels, which is decent for indoor use but not great in direct sunlight because the backlight brightness is only around 200 to 400 nits. The viewing angles are specified as 6 o'clock, meaning the best viewing direction is from the bottom, but in practice, the horizontal viewing angle is about 60 degrees to the left and right, and the vertical viewing angle is about 40 degrees up and 60 degrees down. The response time of the liquid crystal cells is typically around 10 to 20 milliseconds for rise and fall, which is fast enough for static images and slow animations but not for high-speed video. The interface uses a 4-wire or 5-wire SPI bus, with pins for CS (chip select), DC (data/command), MOSI (master out slave in), SCK (serial clock), and optionally MISO (master in slave out) for reading back data. The SPI protocol supports up to 80 MHz in theory, but most microcontrollers are limited to 40 MHz or less. The display controller has a built-in GRAM (graphics RAM) of 240x320x18 bits, which is about 1.38 megabits, or 172 kilobytes, so the entire frame buffer is stored on the chip itself, meaning you don't need external RAM. The pixel format can be set to 12-bit, 16-bit, or 18-bit, but 16-bit is the most common because it balances color quality and data transfer speed. In 16-bit mode, each pixel is represented by 5 bits for red, 6 bits for green, and 5 bits for blue, which gives you 32 shades of red, 64 shades of green, and 32 shades of blue, for a total of 65,536 colors. The human eye is more sensitive to green, so the extra bit for green makes sense. The color gamut of these TFT displays is usually about 60% to 70% of NTSC, which is typical for low-cost LCDs. The gamma correction is set by the controller and can be adjusted via registers, but most users leave it at default. The display supports hardware rotation, meaning you can set the orientation to portrait or landscape by changing a register value, which changes the scanning direction of the pixels. The command set includes over 100 instructions for setting windows, scrolling, brightness, and sleep modes. The sleep mode current is under 10 microamps, which is crucial for battery-powered devices. The module often includes a resistive touch panel as an option, which adds about 1 mm to the thickness and requires a separate touch controller like the XPT2046. The resistive touch panel has a resolution of about 4096x4096 points, but the accuracy is limited by the analog-to-digital converter and the physical construction, so you typically get about 1% accuracy. The touch panel requires a 4-wire or 5-wire interface, and the response time is around 10 milliseconds. The display module is usually sold with a breakout board that has a 0.1-inch pitch header, making it easy to breadboard. The operating voltage for the logic is 2.8 to 3.3 volts, but the backlight can take up to 5 volts if you use a resistor to limit current. The IO pins are 5-volt tolerant on some modules, but it's safer to use a level shifter if you're using a 5-volt microcontroller. The temperature range is typically -20 to +70 degrees Celsius for storage and -10 to +60 degrees Celsius for operation. The display uses a TN (twisted nematic) LCD panel, which is the cheapest type, so the viewing angles are not as wide as IPS (in-plane switching) panels, but the response time is faster. The polarizer is matte or glossy depending on the model, but most budget modules use a glossy finish that reflects light more. The backlight diffuser is a thin plastic sheet that spreads the light evenly, but you can sometimes see hot spots near the edges if the LEDs are not perfectly aligned. The glass thickness is about 0.5 mm for the top and bottom substrates, and the liquid crystal layer is about 5 microns thick. The pixel layout uses a delta or stripe arrangement, but stripe is more common for TFT because it gives better color fidelity. The resolution of 240x320 is also used in many other small displays like 2.8 inch, 3.5 inch, and 4.0 inch versions, but the pixel density changes with size. For example, a 2.8 inch 240x320 display has a PPI of about 143, while a 3.5 inch version has about 114 PPI. So the 3.2 inch sits in the middle, offering a good balance between readability and physical size. The active area dimensions are 48.6 mm by 64.8 mm, which is roughly the size of a credit card but slightly smaller. The module weight is about 15 to 20 grams, depending on whether it has a touch panel. The PCB is usually a 2-layer board with a green solder mask and gold-plated pads. The display driver IC is bonded to the glass using chip-on-glass (COG) technology, which reduces the number of external components. The IC has a built-in oscillator, so you don't need an external crystal, but you can provide an external clock if needed. The SPI interface is compatible with 3.3-volt logic, but some controllers like the ESP32 use 3.3-volt logic natively, so no level shifting is required. The data transfer rate for a full 240x320 frame in 16-bit color is 240 * 320 * 2 = 153,600 bytes. At 20 MHz SPI clock, which is 2.5 MB per second theoretical, the transfer time is about 61 milliseconds, but the actual time is longer due to command overhead and delays. The ILI9341 has a feature called "write cycle" that allows you to send pixel data continuously without resending commands, which speeds up the process. The display can be used in portrait or landscape mode, but the physical orientation of the module is usually portrait. The connector is a 14-pin or 16-pin header with 0.1-inch spacing, and the pinout is standardized across many modules, but you should always check the datasheet. The power supply for the logic is separate from the backlight, so you can turn off the backlight to save power without losing the image. The display has a built-in voltage regulator for the LCD driver, so you only need to provide 3.3 volts. The current draw for the logic is about 5 to 10 mA, and the backlight draws 20 to 40 mA depending on the brightness setting. The total power consumption is around 100 to 150 mW at typical brightness, which is low enough for battery-powered projects. The display can be used with a wide range of microcontrollers, and there are libraries available for Arduino, CircuitPython, and MicroPython. The SPI interface is simple enough that you can write your own driver if you want. The resolution of 240x320 is also suitable for displaying simple user interfaces, such as menus, buttons, and graphs. The pixel density of 125 PPI means that text at 12-point font size will be about 16 pixels tall, which is readable but not crisp. For icons, you can use 16x16 or 32x32 pixel images, which will look blocky but functional. The display is not suitable for high-resolution images or video, but it works well for data visualization, such as temperature sensors, heart rate monitors, and oscilloscopes. The refresh rate of 60 Hz is smooth enough for animations, but you will see flicker if you update the entire screen too slowly. The display supports partial update modes, where you only update a small window, which can reduce the data transfer time. The ILI9341 also supports hardware scrolling, which allows you to shift the display content vertically without rewriting the entire frame. The color depth of 16-bit is sufficient for most applications, but you will see color banding in gradients because there are only 32 shades of red and blue. The display can also be used in 8-bit mode, where you only send 8 bits per pixel, but that reduces the color palette to 256 colors. The resolution of 240x320 is also known as QVGA, and it's a standard resolution that many graphics libraries support. The display module is often used in handheld devices, such as game consoles, MP3 players, and digital cameras. The 3.2 inch size is a sweet spot for portable devices because it's large enough to show information but small enough to fit in a pocket. The module is also used in industrial applications, such as barcode scanners, medical devices, and control panels. The display has a long lifespan, typically 50,000 hours for the backlight LEDs, which is about 5.7 years of continuous use. The LCD panel itself does not degrade over time, but the polarizer can yellow with UV exposure. The display is not waterproof, but you can add a protective cover if needed. The module is RoHS compliant and lead-free. The resolution of 240x320 is not going to win any awards for sharpness, but it's a proven, reliable, and cost-effective solution for embedded systems. The price of the module is usually under $10, making it one of the cheapest TFT displays available. The SPI interface is also easy to troubleshoot with a logic analyzer because the signals are slow and simple. The display can be driven by a 16 MHz Arduino Uno, but the frame rate will be lower because of the limited SPI speed. With an ESP32 at 40 MHz SPI, you can achieve smooth animations. The display also supports a parallel interface on some modules, but the SPI version is more common because it uses fewer pins. The resolution of 240x320 is also used in some e-paper displays, but TFT is much faster for updates. The viewing angle of the TN panel is the main limitation, but you can mitigate it by mounting the display at an angle. The color reproduction is also not as accurate as IPS, but it's good enough for most applications. The display has a built-in gamma correction curve that you can adjust to improve contrast. The backlight brightness can be controlled by PWM (pulse width modulation) on the LED pin, which allows you to dim the display to save power. The PWM frequency should be above 200 Hz to avoid visible flicker. The display module also includes a capacitive touch option on some versions, but the resistive touch is more common for low-cost modules. The touch panel adds about $2 to $3 to the cost. The display resolution of 240x320 is also used in some smartwatches, but those usually have a higher PPI because the screen is smaller. The 3.2 inch size is also used in automotive dashboards for displaying speed, fuel, and temperature. The display is not automotive-grade, so it may not withstand extreme temperatures or vibration. The module is also used in educational kits for teaching embedded systems and graphics programming. The resolution is low enough that you can easily generate graphics with a simple microcontroller, but high enough to create a usable interface. The pixel density of 125 PPI is comparable to a 15-inch monitor at 1024x768 resolution, which was common in the early 2000s. The display is also used in retro gaming projects because it can emulate classic game consoles like the Game Boy Advance, which had a 240x160 resolution. The 3.2 inch size is slightly larger than the original Game Boy Advance screen, which was 2.9 inches. The display can also be used for displaying QR codes, barcodes, and simple text messages. The resolution is also suitable for showing a digital clock with large digits. The display has a response time of about 20 milliseconds, which is fast enough for scrolling text but not for fast-paced games. The display also has a sleep mode that reduces power consumption to under 1 mW, which is useful for battery-powered devices that need to wake up periodically. The display module is often sold with a microSD card slot, which allows you to store images and fonts. The microSD card uses SPI as well, so you can share the same bus with the display. The display resolution of 240x320 is also used in some digital photo frames, but those are usually larger. The 3.2 inch size is also used in portable oscilloscopes and logic analyzers. The display is also used in weather stations for showing temperature, humidity, and pressure. The resolution is also sufficient for displaying a simple map with a few landmarks. The display has a built-in font library in some drivers, but most users prefer to use custom fonts. The display can also be used for displaying sensor data in real-time, such as a graph of temperature over time. The refresh rate of 60 Hz is smooth enough for a real-time graph. The display also supports multiple windows, which allows you to display different types of data in different areas. The display resolution of 240x320 is also used in some barcode scanners and handheld terminals. The 3.2 inch size is also used in some medical devices, such as glucose meters and blood pressure monitors. The display is also used in some home automation systems for controlling lights and thermostats. The resolution is also suitable for displaying a simple menu system with a few options. The display has a contrast ratio of about 500:1, which is good enough for indoor use. The display also has a wide color gamut for a TN panel, but it's still limited compared to IPS. The display can also be used in dark environments because the backlight is bright enough. The display resolution of 240x320 is also used in some educational toys and learning devices. The 3.2 inch size is also used in some handheld GPS devices for showing maps and coordinates. The display is also used in some digital cameras for showing the preview image. The resolution is low enough that the image will look pixelated, but it's good enough for framing a shot. The display also has a built-in frame buffer, so you can take a screenshot and save it to a microSD card. The display can also be used for displaying a simple animation, such as a bouncing ball. The refresh rate of 60 Hz is smooth enough for simple animations. The display also supports hardware acceleration for drawing lines, circles, and rectangles. The ILI9341 has a built-in drawing engine that can draw these shapes without using the microcontroller's CPU. The display resolution of 240x320 is also used in some industrial control panels for showing machine status. The 3.2 inch size is also used in some barcode scanners for showing the scanned code. The display is also used in some handheld gaming consoles for showing the game graphics. The resolution is low enough that the graphics will look blocky, but it's good enough for retro games. The display also supports multiple color depths, so you can choose between 16-bit, 18-bit, or 12-bit color. The 12-bit color mode uses 4 bits per channel, which gives you 4096 colors, but the quality is lower. The display also supports a sleep mode that reduces power consumption to under 10 microamps. The display module is also available with a capacitive touch panel, which is more responsive than resistive touch. The capacitive touch panel uses a separate controller like the FT6206 or the GT911. The capacitive touch panel supports multi-touch, but the display resolution is low enough that multi-touch is not very useful. The display resolution of 240x320 is also used in some smart home devices, such as smart thermostats and smart locks. The 3