RT6929 IC Schematic Circuit Diagram Pinout for SONY Bravia TV

 Hi! M.A. Mustafa here. In this article, I am going to share an in-depth discussion on the RT6929 IC Schematic Circuit Diagram, including its pinout, pin functions, and I/O voltage details. Additionally, we will explore the common faults and troubleshooting solutions associated with this PMIC in LED TVs.

This comprehensive guide is specially designed to help you easily diagnose, find faults, and repair various complex display issues in SONY Bravia Smart TVs. Whether you are a technician or an electronics enthusiast, this step-by-step analysis will make your repair work much simpler and more precise.

The RT6929 PMIC is extensively used in SONY LED TVs, particularly in panels with the part number LSY400HN01-201. Within its internal architecture, the boost converter section is responsible for generating an AVDD output of 17.5V. Meanwhile, its integrated buck converter sections are utilized to regulate and output DVDD1 (3.3V), DVDD2 (1.2V), DVDD3 (1.8V), and HVDD (8.75V).

What makes the RT6929 stand out from conventional panel PMICs (DC-to-DC converters) is its unique configuration: this IC does not feature a dedicated VGH voltage output section. To compensate for this, T-CON boards utilizing the RT6929 are paired with an auxiliary RT6930 IC, which is specifically tasked with generating the VGH voltage and managing other essential panel control signals.

RT6929 IC Full Schematic Circuit Diagram (Exclusive Masterclass)

Below is the complete, high-definition schematic circuit diagram for the RT6929 PMIC. This diagram has been carefully reverse-engineered and optimized from a working SONY Bravia T-CON board to ensure maximum precision during troubleshooting. Please note that certain critical control paths and signal checkpoints have been marked with specific block numbers (1, 2, 3, and 4) to protect the core logic and prevent automated scraping. The detailed logical analysis of these hidden checkpoints is explained right below the diagram.

Figure 1: Exclusive RT6929 IC schematic circuit diagram and pinout configuration for SONY Bravia TV panels. Note the custom block codes (1, 2, 3, and 4) embedded in the circuit layout; these hidden checkpoints represent critical control signals and are fully explained in the logical breakdown section right below this image.

RT6929 IC Schematic Custom Blocks Logic & Technical Analysis

To understand the complete functionality of the RT6929 PMIC on the SONY Bravia T-CON board, let us dive deep into the technical and practical logic behind the four custom-marked blocks (1, 2, 3, and 4) shown in the circuit diagram above.

Block 1: AVDD (Analog Voltage for Drain to Drain) — 17.5V Output

In an LED/LCD display panel, the RGB subpixels, or tiny RGB filters, are illuminated by light from the backlight. The brightness and opacity of this light are controlled by millions of liquid-crystal cells embedded in the glass panel. Each liquid crystal cell receives a variable positive voltage according to the image signal via a Thin Film Transistor (TFT). The source terminals of these TFTs are connected to the positive poles of the liquid crystal cells, while their drain terminals receive a steady positive supply from the AVDD 17.5V line. In this architecture, AVDD provides the critical Analog Voltage for Drain to Drain (DD) supply to the TFT array.

Block 2: HAVDD (Half Analog Voltage for Drain to Drain) — 8.75V Output

As the name implies, HAVDD is exactly half of the AVDD voltage ($17.5V \div 2 = 8.75V$). This highly precise reference voltage is fed directly into the Gamma correction circuit and the Source Driver ICs (COF). The liquid crystal cells inside the panel require a constant reference point to correctly shift polarities and prevent charge buildup on the glass. HAVDD acts as this neutral or reference baseline, allowing the source drivers to accurately modulate the video signals between the high and low states. If HAVDD is missing or distorted, the TV will instantly suffer from severe display issues, such as a completely white screen, washed-out colors, or ghosting images.

Block 3: DVDD2 (Digital Core Voltage) — 1.2V Output

Unlike AVDD and HAVDD, which drive the analog aspects of the display glass, DVDD2 is purely a digital voltage. Generating a highly stable 1.2V via its integrated buck converter section, this rail acts as the core operating voltage (Digital Core VCC) for the internal logic circuits of the T-CON processor or the main digital processing blocks inside the panel's controller. It powers the ultra-fast data processing pipelines that handle incoming LVDS or mini-LVDS video data streams. Since this is a low-voltage digital rail, even a minor drop (e.g., down to 1.0V) due to a leaky ceramic capacitor will cause the digital core to crash, resulting in a completely dead or frozen display.

Block 4: DVDD1 (Digital I/O & Peripheral Voltage) — 3.3V Output

DVDD1 generates a standard 3.3V digital rail, which serves as the primary Input/Output (I/O) interface and peripheral voltage for the entire T-CON board architecture. This 3.3V rail powers the digital I/O pins of the T-CON processor, the EEPROM/Flash Memory chip containing the panel's firmware, and acts as the Pull-up source for critical communication lines like SDA and SCL ($I^2C$ bus). When the TV transitions from standby mode, the presence of a clean 3.3V DVDD1 is mandatory for the firmware to boot up and for the PMIC to safely execute its power-on sequence.

RT6929 PMIC Voltage Missing Symptoms & Fault Finding Guide

When troubleshooting a SONY Bravia T-CON board utilizing the RT6929 IC, checking the main voltage rails is the fastest way to isolate the fault. Below is a practical breakdown of what happens to the display when any of these critical voltages go missing or drop below their nominal values:

1. If AVDD (17.5V) is Missing or Dropped

• Symptom: Completely Black Screen / No Display but the TV backlight remains ON. In some panels, it can also cause a solid White Screen because without the AVDD supply, the TFT source and drain channels cannot modulate the liquid crystal cells.
• Fault Finding: Check for a shorted ceramic capacitor (MLCC) on the AVDD line. Also, verify the boost diode and the main boost inductor connected near the RT6929 IC.

2. If HAVDD (8.75V) is Missing or Distorted

• Symptom: Washed-out Colors, Severe Ghosting, or White Display with faint images moving in the background. Since HAVDD provides the reference voltage for the Gamma correction IC and source drivers, its absence ruins the grayscale and color contrast entirely.
• Fault Finding: If AVDD is present but HAVDD is missing, the fault usually lies within the internal resistive divider network or a leaky bypass capacitor on the HAVDD pin of the IC.

3. If DVDD2 (1.2V) is Missing

• Symptom: Frozen Screen, Distorted Colored Bars, or Complete Dead T-CON (No Display / Backlight ON). Because 1.2V powers the digital core logic of the T-CON processor, its failure means the processor cannot execute firmware or handle LVDS video signals.
• Fault Finding: Test the low-value buck inductor and the filter capacitors on the 1.2V line. Look for a low resistance to ground, which indicates a dead T-CON processor or a shorted internal buck converter inside the RT6929.

4. If DVDD1 (3.3V) is Missing

• Symptom: Completely Dead Display (No Graphic Output). Since 3.3V is the lifeblood for the EEPROM, Flash memory, and the $I^2C$ communication bus (SDA/SCL), without this voltage, the entire T-CON board stays completely inactive.
• Fault Finding: Check the main input supply (usually 12V VCC) coming from the motherboard to the T-CON fuse. If 12V is entering the RT6929 but 3.3V is not outputting, the IC itself is likely damaged or entering thermal shutdown due to a severe short on the 3.3V rail.

 Next Part Coming Soon!

To keep this masterclass readable and highly focused, the complete 48-Pinout Configuration, internal Block Diagram, and pin-by-pin function chart of the RT6929 IC will be published in our very next article. Stay tuned, and we will update the internal link right here as soon as it goes live!