Inspect for "swollen tops" on the 5V/12V output capacitors. Replace with low-ESR equivalents. LED Driver Circuit / Open LED Strip
(also seen as part of the series by manufacturers like TPV/AOC) typically refers to a Power/Inverter (P/I) board used in various LCD monitors, including certain Acer and Dell models. In a schematic for this type of board, "VA" often refers to the Video Amplifier or a specific Voltage Rail (e.g., +12V or +5V outputs) directed toward the video processing section.
The old schematic relied on a to sequence the output enable. When 3.3V_ALW came up, a capacitor would slowly charge, turn on a MOSFET pass transistor, and—250ms later—the 1.8V rail would appear. ilpi354 va schematic upd
Originally, a single ceramic 22µF cap was recommended on VOUT. The new schematic shows in parallel. Why? The ILPI354 now performs a capacitive load calibration during power-on. It measures the total output capacitance and adjusts its internal current limit slope. This prevents the dreaded "inrush current latch-off" when driving high-capacitance loads (like a bank of DDR termination regs).
Fuse, bridge rectifier, and main filter capacitor ( Cicap C sub i Switching Controller: IC for managing the power conversion. Transformer: Steps down the voltage. Output Diodes/Capacitors: Filters the output voltage ( +5Vpositive 5 cap V and usually 12V12 cap V 18V18 cap V for LED driver).
(utilizing components like CP315) to prevent current spikes during the initial power-up of the video and backlight stages. EDN - Voice of the Engineer Common Failure Points to Check In a schematic for this type of board,
