The Vestel 17IPS72 is a widely used power supply unit (PSU) found in many budget LED TVs, including brands like JVC, Toshiba, Hitachi, and Bush. Core Circuit Overview The 17IPS72 typically consists of two main stages:
PFC (Power Factor Correction): Regulates the input power from the mains to provide a stable +400V DC output for downstream components. It often utilizes a FAN7529 controller chip and a dedicated MOSFET on a heatsink.
Secondary Outputs: Converts the high voltage into lower rails required by the TV mainboard and backlight. Common outputs include: +12V (Main supply for logic and audio). +24V (Often used for backlight driving). +12V_STBY (Standby voltage for the processor). Common Faults & Repair Steps
If your board is "dead" (no standby lights), follow these diagnostic steps based on common failure points: 17IPS72P Power Supply Schematic | PDF - Scribd
The Vestel 17IPS72 is a widely utilized Power Supply Unit (PSU) found in a variety of budget-friendly LED TVs, including brands like JVC, Panasonic, Telefunken, and Toshiba. Understanding its schematic is vital for technicians, as these boards are often the primary point of failure in modern television sets. Overview of the 17IPS72 Schematic
The 17IPS72 is a Switched-Mode Power Supply (SMPS) designed to convert high-voltage AC mains into stable DC rails for the TV's internal components. Key sections of the schematic include: 17ips72 schematic work
EMI Filter and Rectification: The circuit starts with an input stage featuring fuses, EMI filters (LF1, LF2), and a bridge rectifier (D1) to convert AC to raw DC.
PFC (Power Factor Correction): Most 17IPS72 variants include a PFC stage to improve efficiency. This involves a PFC Controller IC, a large PFC MOSFET (typically on a heatsink like HS1), and a boost inductor to maintain a steady +400V rail.
Secondary Voltage Rails: The board generates several regulated low-voltage outputs, typically +3.3V (standby), +5V, and +12V.
LED Driver Stage: A specialized section of the circuit boosts voltage specifically for the LED backlights, often controlled by an IC like the MP3394S. How the Schematic Works
The 17IPS72 operates through high-frequency switching. The control IC monitors the output voltages and adjusts the "on-time" of the MOSFET switches to maintain stability. The Vestel 17IPS72 is a widely used power
Standby Mode: Upon receiving AC, the board first generates a low-power standby voltage to run the TV's infrared receiver and main processor.
Power-On: When the TV is turned on, the main processor sends a signal to the 17IPS72 to activate the PFC and main switching stages, providing full power to the 12V and LED backlight rails.
Regulation: Feedback loops (usually using optocouplers) ensure that if a rail drops under load, the controller increases the switching frequency to compensate. Common Faults and Troubleshooting
Technicians often encounter specific failures on the 17IPS72 board: 17IPS72 Repair
While the exact pinout can vary slightly between OEM versions (e.g., Rohm, STMicro, or Matsushita variants), a standard 36‑pin or 48‑pin QFP package follows a logical pattern. Part 2: The Critical Pinout – Mapping the
Below is a generalized pinout table for reference when performing 17IPS72 schematic work:
| Pin Group | Pin Numbers (Typical) | Function | Signal Type | |-----------|----------------------|----------|--------------| | Power Input | 1, 2, 35, 36 | Vcc (5V logic) & Vm (12V motor supply) | Power | | Charge Pump | 5, 6 | CP1, CP2 – external capacitor connections | Analog | | Phase U Out | 14, 15 | U+ (high-side), U- (low-side return) | Output | | Phase V Out | 17, 18 | V+ / V- | Output | | Phase W Out | 20, 21 | W+ / W- | Output | | Current Sense | 23, 24 | ISENSE – external resistor to GND | Analog | | Hall Emulation | 26, 27, 28 | H1, H2, H3 – synthesized Hall signals | Output | | FG (Speed) | 30 | Frequency Generator – tachometer pulse | Open drain | | RD (Lock) | 31 | Rotation Detect – high when motor at target speed | Open drain | | PWM/Reference | 32 | VREF – speed control voltage input | Analog | | Brake/Enable | 33 | BRK – active high brake | Digital |
Pro tip for 17IPS72 schematic work: Always verify pins 12, 25, and 34 as GND. Many failed repairs are due to assuming a different ground pin.
Each phase pair (U+/U-, V+/V-, W+/W-) goes through a series of protection diodes and then directly to the spindle motor connector. Use a multimeter in continuity mode to map which pin corresponds to which motor winding.
Typical tasks with the schematic:
Pair the schematic with a boardview (.BRD, .CAD, .FZ) to see physical component locations.
The LG 17IPS72 is a standardized power supply unit (PSU) manufactured for LG. It typically handles:
EN_GFX comes from the GPU’s own power sequencer. Also, check the FB (Feedback) resistors for the core voltage. A single drifted resistor (e.g., 1% tolerance part drifted to 5%) can cause the GPU to output 0.8V instead of 1.05V, preventing the driver from loading.