Inx In518 Ic Pinout Diagram Today
Below is an overview of the critical pin layout sections as mapped out in typical T-CON application circuits: Pin Zone / Number Pin Mnemonic / Label Electrical Function & Signal Description Typical Value / Level VIN / VCC
Pins with no internal electrical connection, usually left floating or soldered to isolated PCB pads for structural stability. How to Read the In518 Pinout Diagram
In many Samsung and Innolux panels, internal gate lines (CKV1, CKV2, CKVB1, CKVB2) develop insulation breakdowns inside the glass substrate, shorting the high-voltage VGH and VGL rails together. Technicians isolate this by carefully tracking down the side-panel gate tracks and using a razor to sever the conflicting CKV trace lines on the PCB. This breaks the short, allows the INX IN518 to leave protection mode, and completely restores image playback. Replacement and Solder Specifications Inx In518 Ic Pinout Diagram
| Pin | Name | Function Description | | :--- | :--- | :--- | | 1 | VCC | : Provides the main input voltage for the chip, typically 12V from the T-CON board. | | 2 | GND | Ground : The common ground reference for the chip and all its generated outputs. | | 3, 4 | AGND | Analog Ground : Dedicated ground pins for the chip's sensitive internal analog circuitry, separate from noisy digital grounds for better stability. | | 5, 6 | EN | Enable : Receives an enable signal (often from the timing controller like IN2812A or a power-on sequence control chip) to activate the IN518 and start all its voltage outputs. | | 7, 8 | LX1, LX2 | Switching Node : Connected to the internal power MOSFET switch and the external inductor. These are the primary output pins for the boost converter, generating VAA (typically +17.9V for source driver ICs). | | 9, 10 | FB1, FB2 | Feedback : Senses the output voltage and provides a feedback signal to the chip's internal error amplifier for precise voltage regulation. | | 11, 12 | COMP | Compensation : Connected to an external RC network (resistor and capacitor) for stabilizing the chip's internal control loop, ensuring stable operation. | | 13, 14 | VGL | Negative Gate Voltage : An important output that provides the negative gate-off voltage for the LCD panel's TFT transistors, typically around -8V to -12V. | | 15, 16 | VGH | Positive Gate Voltage : Provides the high positive gate-on voltage necessary to activate the TFT's switching, typically ranging from +25V to +30V. | | 17, 18 | VGH_ON | Gate On Drive : Pins dedicated to generating the controlled high-voltage on-drive signal for the gate driver ICs. | | 19 | AVDD_VAA | Analog Power Supply : Provides the core voltage for analog circuitry in the source driver ICs and gamma reference buffer, typically around 15V-18V. | | 20, 21 | VCOM | Common Voltage : Generates the stable reference voltage for the liquid crystal layer, typically around 7.3V, requiring high precision for consistent image quality. | | 22, 23 | VDD | Digital Logic Supply : Provides a lower voltage (e.g., 3.3V) for the T-CON board's digital logic circuits, processors, and memory chips. | | 24 | PWR_OK | Power Good : A logic output signal that goes high (e.g., 3.3V) to indicate that all power supply rails are within their nominal operating ranges. | | 25, 26 | SS | Soft-Start : Connected to an external capacitor to control the soft-start time, which limits inrush current during startup for smooth power-up. | | 27, 28 | ISENSE | Current Sense : Monitors the current through the external power path to the LCD panel for overcurrent protection. | | 29-31 | NC | No Connect : Unused pins with no internal connection. | | 32-34 | VIN | Input Voltage : Additional input voltage pins connected in parallel with Pin 1 (VCC) for improved power distribution and current handling. | | 35-37 | LX3, LX4, LX5 | Switching Node : Additional switching nodes (like LX1 & LX2) used for generating other necessary voltages (e.g., VGL, VGH, VDD). | | 38-40 | BST | Bootstrap : Connected to external bootstrap capacitors (typically C0402 or C0603) that provide the necessary voltage to drive the high-side internal MOSFETs. |
Depending on your exact application circuit (such as dual-channel signaling or push-pull configurations), Pin 5 acts either as a secondary output driver or is left as a "No Connect" (NC). If specified as NC in your datasheet variant, leave it physically floating on the PCB. Pin 6: COMP (Frequency Compensation) Below is an overview of the critical pin
Output voltage sense or direct low-dropout regulation terminal depending on the exact chip sub-variant. 3. How the IN518 Operates: Internal Architecture
The IN518 is known to be a common point of failure in LCD displays, often due to overheating or power surges. Its failure typically leads to a variety of image-related issues. Below is a structured troubleshooting guide based on aggregated community knowledge, which also includes critical safety precautions. This breaks the short, allows the INX IN518
Improper layout is the most common reason for DC-DC converter failure, excessive noise, or poor voltage regulation. Use these guidelines alongside the pinout diagram:
Designed to filter out high-frequency electromagnetic interference (EMI). Inx In518 IC Pinout Diagram Layout