MIPI INTERFACE

MIPI Bandwidth Calculator

MIPI Interface Bandwidth Calculator

Calculate required bandwidth including protocol and embedded data overhead for CSI-2/DSI systems.

Horizontal Pixels

Vertical Pixels

Frame Rate (FPS)

Bits per Pixel (bpp)

Embedded Data Overhead (%)

Additional data for gain, exposure, etc.

Total Throughput:

MIPI DSI Bandwidth Calculator

MIPI DSI Bandwidth Calculator

Metric	Value	Formula / Basis

Calculation Mode: Precise Timing Percentage Estimate

Active Width

Active Height

Color Depth (bpp) 16 18 24

Data Lanes 1 2 4

HFP

HSYNC

HBP

VFP

VSYNC

VBP

Blanking Percentage (%)

15%

Refresh Rate (Hz)

TFT Display Timing

TFT Display Timing Visualizer

Watch the dot scan across the virtual frame to see how PCLK, HSYNC, VSYNC, and DE work together to draw an image on a screen.

Frame Scanning Area

DE Signal:

Speed:

Sync (H/V)

Back Porch

Active Data (DE)

Front Porch

Live Logic Signals

PCLK: Pixel Clock. Pulses once for every single pixel position.

DE: Data Enable. High ONLY when scanning the Active Data area.

HSYNC: Horizontal Sync. Pulses to start a new row.

VSYNC: Vertical Sync. Pulses to start a new frame.

What do these terms mean?

Front Porch (FP)

A brief delay after the active pixel data finishes, but before the sync pulse occurs. It gives the hardware a moment to stabilize.

Sync Pulse (HSYNC/VSYNC)

A signal telling the display panel to reset its drawing position back to the beginning of the next line (HSYNC) or back to the top-left (VSYNC).

Back Porch (BP)

A brief delay after the sync pulse ends, but before the actual pixel data begins. It provides settling time.

Active Area / Data Enable (DE)

The portion of the timing cycle where actual, visible pixels are drawn on the screen. The DE signal goes HIGH.

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How does a TFT Panel Work?

A Thin-Film-Transistor (TFT) display consists of a massive grid of pixels. To display an image, the screen can't light up all pixels simultaneously. Instead, it draws them one by one, scanning from left to right, and top to bottom (exactly like the visualizer above). The timing signals act as the conductor of this orchestra, ensuring the display panel knows exactly when and where to place the incoming color data.

GMSL2 Deserializer to TFT Signals

In modern systems (like automotive infotainment systems or remote industrial displays), video is often transmitted over long distances using a high-speed serial link like GMSL2 (Gigabit Multimedia Serial Link). A Serializer compresses the video at the source, sends it over a single cable, and a Deserializer translates it back into signals the TFT panel understands.

Here are the primary signals passed from the GMSL2 Deserializer to a traditional parallel RGB TFT panel:

1. Timing & Synchronization

• PCLK (Pixel Clock): The continuous heartbeat that clocks data into the display.
• VSYNC & HSYNC: The structural boundaries of the frame and lines.
• DE (Data Enable): Gates the active color data so the screen only draws when valid.

2. Video Data (RGB)

Parallel data lines carrying the color info. For a 24-bit display (RGB888), there are 24 physical wires representing Red, Green, and Blue intensities for the exact pixel currently being drawn.

3. Control Interfaces

Usually an I2C or SPI interface passed through the GMSL link. This allows the main processor to configure panel registers, adjust gamma, or read diagnostic information.

4. Backlight & Power

Hardware signals, often including a PWM (Pulse Width Modulation) pin to control screen brightness, an Enable pin to turn the display on/off, and standard power rails (VDD).

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The Brains of the Panel: The TCON

It's important to note that the signals from the GMSL2 Deserializer don't connect directly to the glass pixels. Instead, they feed into an IC usually located directly on the display module called the Timing Controller (TCON). The TCON acts as the ultimate conductor for the panel. It takes the standard logic-level signals (PCLK, Syncs, DE, and RGB data) and translates them into the precise, high-voltage analog signals required by the panel's Source and Gate drivers. If the TCON doesn't receive a valid DE signal (try toggling it off in the visualizer above!), it won't instruct the drivers to update the screen, resulting in a blank display.

*Note: Many modern displays use MIPI DSI or eDP instead of parallel RGB, which packages these timing syncs and data into high-speed data packets. I will add the MIPI DSI and eDP protocol details in the next blog post, stay tuned!

Reference: Click here to learn more about TFT Timing

SMART WATCH TEARDOWN

 

SMART WATCH TEARDOWN

Smartwatches have become an important part of our daily lives. They help us track our fitness, receive notifications, and even make calls. But have you ever wondered what is inside a smartwatch?

In this blog, we will take apart a smartwatch to see its internal components. We will explore the display, battery, sensors, processor, and other key parts. This teardown will help us understand how a smartwatch works and how all the small components fit together in a compact design.

Let’s begin the teardown and discover the technology inside a smartwatch!

Before Opening

Here’s a breakdown of the components:

Battery (LQ-S1) – This is a 3.7V, 380mAh rechargeable lithium battery. It powers the smartwatch and is designed for low-power operation.

Main Circuit Board (PCB) – This green board contains the key electronic components.

1: VIBRATION MOTOR

2: SPEAKER

3: PCB ANTENNA

4: MINI USB CONNECTOR

5: BATTERY CONNECTOR

6: SIM SLOT

7: CAMERA

8: SD CARD SLOT

9: POWER SWITCH

10:GSL 2036 Touch Controller IC

Touch Controller IC

11,12 DISPLAY CONNECTORS

13. MEDIATEK PROCESSOR (MT6260)

PROCESSOR

Datasheet Link: Click here

14: CRYSTAL

15: POWER IC MS5525

16: MIC

17: DISPLAY

TOCUH SCREEN

PCB TOP SIDE

Conclusion:

Through this teardown, we explored the internal components of a smartwatch and understood how different parts work together. The battery, camera, display, main processor (MT6260), SIM card slot, vibration motor, and other key components make the smartwatch functional and compact.

This teardown gives us a better idea of the engineering behind smartwatches. It shows how manufacturers fit advanced technology into such a small device while balancing performance, power efficiency, and connectivity.

Hope you found this teardown interesting! Stay tuned for more tech breakdowns. 

Automotive Ethernet Interface Basics

 

Automotive Ethernet Interface Basics:

In this article, we’ll revisit how Automotive Ethernet interfaces work and provide an overview of its various types, highlighting their key differences and applications.

BLOCK DIAGRAM :

Image Reference OPEN Alliance

MDI (Media Dependent Interface): 

MDI defines how signals are transmitted and received over Ethernet cables, especially in automotive networks using Single-Pair Ethernet

PHY (Physical Layer) Chip: The signal from the PHY chip is transmitted over twisted-pair cables.

DC Blocking / AC Coupling Capacitor: Placed in series between the PHY and the Ethernet cable to block any DC bias and protect the system. AC Coupling is realized by 100nF Coupling Capacitor to form a high pass filter together with 50Ohm termination on each line.

Signal Integrity: The capacitor ensures that only the desired AC signal (which carries data) is passed to the PHY, while any DC bias is blocked.

CMC (Common Mode Choke) is used to reduce electromagnetic interference and noise, ensuring reliable data transmission in noisy automotive environments.

Common mode Termination :

For common-mode termination, a split termination consisting of two 1kΩ resistors and a 4.7nF capacitor, with a 100 kΩ resistor to GND, can be connected to the signal lines between the coupling capacitors and the connector. For reasons of symmetry, the tolerance of the two 1 kΩ resistors should be within ±1 %. The power rating should be higher than 0.4 W (anti-surge) in order to survive EMI disturbances. They match the impedance of the Ethernet cable, prevent signal reflections, and ensure that the data stays accurate. Those are not be shown in the image above.

Automotive Ethernet Standard	IEEE Standard	Speed	Media	Use Case
100BASE-T1	IEEE 802.3bw	100 Mbps	Single-Pair Ethernet (SPE)	Low-speed applications (e.g., sensors, body control modules)
1000BASE-T1	IEEE 802.3bp	1 Gbps	Single-Pair Ethernet (SPE)	Infotainment, ADAS, high-speed sensor networks
10GBASE-T1	IEEE 802.3bm	10 Gbps	Single-Pair Ethernet (SPE)	High-performance applications, autonomous vehicles, HD video
10BASE-T1S	IEEE 802.3cg	10 Mbps	Single-Pair Ethernet (SPE)	Low-bandwidth applications, diagnostic communication
10BASE-T1L	IEEE 802.3cg	10 Mbps	Single-Pair Ethernet (SPE)	Long-reach applications, energy management in EVs

In these standards, T1 refers to a single twisted pair Ethernet media, and the numbers indicate the speed:

• 100BASE-T1: 100 Mbps
• 1000BASE-T1: 1 Gbps
• 10GBASE-T1: 10 Gbps

The S and L denote short and long-range capabilities, with S supporting up to 25 meters for low-speed data transfer and L supporting up to 1000 meters for industrial applications.

Clock Frequency :

In Automotive Ethernet, the PHY’s clock frequency depends on the Ethernet standard and application: 

For 1000BASE-T1, a 125 MHz clock is commonly used.

A crystal oscillator generates the stable clock, sometimes using lower frequencies (e.g., 25 MHz or 50 MHz) to feed into a Phase-Locked Loop (PLL) that multiplies the frequency to achieve the required clock rate.

For example, to transmit 1 Gbps data over Automotive Ethernet using a 25 MHz clock, the clock is typically used to generate timing and encoding signals necessary for high-speed data transmission.                   

Example:

MII (Media Independent Interface):

MII Interface has total Pin counts of 16 for data transfer those are given below

Exploring USB Device Detection with Arduino and USB Host Shield

 

Exploring USB Device Detection with Arduino and USB Host Shield

USB (Universal Serial Bus) is a ubiquitous interface for connecting peripherals to computers and other devices. Arduino, with its versatility and expandability, can be used to interface with USB devices using a USB Host Shield. In this article, we'll explore how to detect and identify USB devices connected to an Arduino using a USB Host Shield.

Hardware Used:

Hardware	Description
Arduino Board	Any compatible Arduino board with sufficient GPIO pins and USB Host Shield library support.
USB Host Shield	A shield specifically designed for USB host functionality, compatible with the selected Arduino board.
USB Devices	Various USB peripherals like mass storage devices, input devices (keyboard, mouse), communication devices, etc.
Serial Monitor	A computer running Arduino IDE or any other serial terminal software for monitoring the Arduino's serial output.
Power Supply	Depending on the connected USB devices and Arduino board, a stable power supply may be required for proper operation.
Optional Components	Breadboard, jumper wires, enclosures, LEDs, resistors, switches, etc., for prototyping and customization.

Hardware Setup:

Arduino sketch:

Verifying the VIP and PID:

Link:

USB ID Database

Arduino sketch:

#include <usbhub.h>

#include <SPI.h>

USB Usb;

USBHub Hub(&Usb);

#define MAX_ROOT_PORTS 2 // Assuming there are 2 root ports on your USB host shield

void setup() {

  Serial.begin(115200);

  while (!Serial); // Wait until Serial is ready

  SPI.begin(); // Initialize SPI

  if (Usb.Init() == -1) {

    Serial.println("Failed to initialize USB Host Shield");

    while (1); // Halt if initialization fails

  }

  Serial.println("USB Host Shield initialized");

}

void loop() {

  Usb.Task();

  delay(100); // Adjust delay as needed

   if (Usb.getUsbTaskState() == USB_STATE_RUNNING) {

    for (uint8_t port = 0; port < MAX_ROOT_PORTS; ++port) {

      USB_DEVICE_DESCRIPTOR dev;

      if (Usb.getDevDescr(port, 0, sizeof(dev), (uint8_t*)&dev)) {

        // Print VID and PID of connected USB devices

        Serial.print("VID: ");

        Serial.print(dev.idVendor, HEX);

        Serial.print(", PID: ");

        Serial.println(dev.idProduct, HEX);

      }

    }

  }

}