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Nie, dziękuję Przekieruj mnie tamA TV TCL 32S615 MT21X7 O DISPLAY TEM UMA RÉGUA COM UM SÓ COF ESTA EM CURTO O CURTO PODE SER NO DISPLAY OU NO COF E SE TEM JEITO
Architecture of the TCL 32S615 panel
• 32 inch FHD LCD, single bottom “source” driver COF bonded to a narrow driver PCB (“régua”).
• Typical power rails: VDD_IO ≈3.3 V, AVDD ≈12-17 V, VGH ≈25-32 V, VGL ≈-6 to ‑12 V, VCOM ≈½ AVDD.
• The COF integrates 384/480 source driver outputs; gate driving is usually generated on the same board.
Typical short-circuit locations
a) Discrete MLCC on the driver PCB – cracked capacitor → AVDD-GND or VGH-GND short.
b) Internal COF failure – ESD or over-voltage punctures the silicon; all rails read a few Ω.
c) TFT glass defect – metal migration or liquid ingress shorts source/gate lines inside the panel.
Diagnostics sequence (non-destructive first)
• Unplug TV, discharge.
• DMM resistance from each rail to GND; document values.
• Visually inspect under 10-20× magnification; look for burnt epoxy, bubbled flex, cracked capacitors.
• If a suspect MLCC is on the shorted rail, lift/replace it and re-measure.
• If no discrete part is guilty, lift the COF power pin(s) or cut the thin supply trace that feeds the COF:
– Short disappears → panel glass side short → panel scrap.
– Short persists on COF side → COF damaged → possible rebond/replacement.
Confirmatory (destructive/advanced) methods
• Low-voltage current-injection: feed 1 V/0.5 A into the shorted rail, use thermal camera or IPA evaporation to find the hot spot.
• Trace-cut isolation on the glass bonding region (last resort).
Interpretation
• MLCC short: replace 0603/0402 capacitor; 5-minute micro-solder job.
• COF short: needs identical COF and ACF hot-bar bonder; only specialised labs, cost often >70 USD.
• Glass short: panel replacement; new 32” TCL panel often >100 USD, usually not stocked, whole TV costs similar.
• Single-COF bottom-driver architecture is now common to cut bezel size; failure modes above are widely reported 2022-2024 in TCL, Xiaomi and Hisense 32–40″ sets.
• Professional repair shops in Asia advertise COF exchange for ~US$50–80, but shipping and no-fix risks apply.
• Manufacturers are moving to COB (Chip-On-Board) gate drivers integrated on the glass; this will make discrete COF replacement impossible, so panel swap will soon be the only path.
– Think of the power rails as water pipes in a house: a cracked capacitor is a leaking tap you can replace; a cracked wall (glass short) means rebuilding the house.
– AVDD and VGH are boosted by a charge-pump on the régua; if either is clamped to GND the boost converter on the mainboard will go into protection, giving the classic “backlight on 1 s → off” symptom.
• High-voltage rails (VGH up to 32 V) and the SMPS primary present shock risk; work with mains disconnected.
• Re-bonding COF requires lead-based ACF adhesives; dispose of residues according to local e-waste rules.
• Respect consumer-safety regulations; never return a TV with bypassed protection fuses.
• Even a successful COF replacement may show column lines or gamma mismatch; warranty your work accordingly.
• Panel part numbers for the 32S615 vary by batch (CSOT vs. BOE); ensure mechanical compatibility before ordering.
• Study CSOT panel datasheets (e.g., ST3151A04-8) for exact rail names/test points.
• Investigate low-cost ACF bonding equipment (pulse-heat vs. constant-heat).
• Follow IPC-7711/7721 rework standards for flex-on-glass assemblies.
The short you observe can originate in three places: a discrete component on the driver board (easiest fix), the COF itself (repairable only with specialised rebond-equipment), or inside the LCD glass (economically unrepairable). Locate the fault by resistance and isolation tests; proceed only if it proves to be off-glass. Otherwise, replacing the entire panel or the TV is the rational option.
