Using the LA-D401P schematic, here is a workflow for common symptoms:
Symptom: Dead TV (No Standby Light)
Symptom: TV Clicks but Won't Turn On
Below is a textual walk‑through of the schematic. Where appropriate, a reference illustration placeholder is suggested for the final article.
Having repaired dozens of these boards, here are the three most common issues the schematic will help you solve:
motherboard schematic is a technical document for the Dell Latitude 3570
. It is an essential resource for technicians performing board-level repairs, such as fixing power issues or replacing burnt components. Laptop schematic Core Technical Specifications According to Laptop-Schematics.com , the LA-D401P motherboard typically features: Processor: Intel Skylake-U series. DDR3L SO-DIMM slots. Integrated UMA or Discrete (N16V-GM-S + DDR3L). Controller (KBC): SMSC MEC1404-NU-GP. Laptop schematic Key Components of the Schematic Guide
A full schematic package for this board generally includes several critical diagnostic tools: Laptop schematic Power Sequence Block Diagram:
A step-by-step map of how power travels through the board after you press the power button. Timing Diagrams:
Shows exactly when specific voltage rails (like +3V, +5V, and VCore) should turn on. SMBUS Block Diagram: la-d401p schematic
Details communication between the PCH (chipset) and the KBC (Keyboard Controller). BoardView File:
A visual map of the physical board that allows you to click a component in the schematic and see exactly where it is located on the motherboard. Basic Diagnostic Tips
If you are using the schematic to troubleshoot a "no power" issue, follow this general sequence identified in repair guides: Input Power:
Check the DC-in jack and the first two protection MOSFETs (labeled 'Q' on the board). Always-On Rails: Ensure the +3.3V and +5V "Always" voltages are present. KBC/EC Power:
The Keyboard Controller (SMSC MEC1404) must be powered and receiving a reset signal.
Check for activity on the BIOS chip (often labeled 'U') pins 1, 2, 5, and 6. Where to Find the Schematic
You can find the LA-D401P schematic and boardview on specialized technician platforms: Laptop-Schematics.com
: Offers the full PDF and BoardView software for the Dell Latitude 3570. Schematics Archive (Telegram)
: A community-driven archive that often hosts free boardview and PDF files for various laptop models. Using the LA-D401P schematic, here is a workflow
: Occasionally hosts technical overviews and partial schematics for similar Compal models. Telegram Messenger Are you troubleshooting a specific symptom , like a laptop that won't turn on or has no display? schematics|boardviews| ARCHIVE – Telegram
The Compal LA-D401P (also known as BDL50) is a motherboard schematic typically used in HP 15-AY series laptops (such as the 15-ay000, 15-ay011nr, etc.). These boards generally feature Intel Braswell or Skylake processors. Technical Summary Manufacturer: Compal Model/Code: BDL50 LA-D401P Associated Device: HP 15-AY Series
Revision History: Common revisions found in documentation include Rev 1.0 (2016-03-04). Key Components: CPU/PCH: Intel Braswell (e.g., Celeron N3060) or Skylake-U.
Memory: DDR3L or DDR4 (depending on the specific sub-version). EC/KBC: ENE KB9022.
Power Rails: Includes standard rails such as +3VLP, +3VALW, +5VALW, and +1.0V_Core. Common Troubleshooting Points Based on technician reports for this specific board:
No Power/Dead: Often traced to the first and second MOSFETs (PQB1/PQB11) or the charging IC (often a BQ-series chip like BQ24725A).
BIOS Issues: This board is known for BIOS corruption. Reflashing the Main BIOS (and sometimes the EC firmware) is a standard repair step for "power on but no display" symptoms.
Water Damage: The areas around the LVDS/EDP connector and the keyboard controller (KB9022) are frequent points of failure due to their proximity to openings. Availability
Schematics and "Boardview" files (typically in .brd or .pdf format) for the Symptom: TV Clicks but Won't Turn On Below
are widely available on technician forums and schematic databases such as BadCaps, VinaFix, and LabOneBiz.
Title: Demystifying the LA-D401P Schematic: A Repair Guide for LG OLED Power Boards
If you are an electronics repair technician or a dedicated DIY enthusiast, you have likely encountered the LA-D401P power board. This component is a staple in many larger LG OLED television models (such as the 55-inch variants). While LG OLEDs are known for their stunning picture quality, their power boards can be susceptible to failure over time due to heat stress.
In this post, we are diving deep into the LA-D401P schematic. We will explore how to read the diagram, identify common failure points, and understand the critical voltage rails that keep your TV running.
If the laptop turns on and off repeatedly, the issue might lie in the "S0" state rails. The schematic reveals the sequence of Power Good (PG) signals. For example, you can check if the +3VALW rail reaches the EC (IT8226VG) and if the EC replies with RSMRST#.
| Symbol | Description | Typical Part | |--------|-------------|--------------| | U2 | Precision error amplifier (e.g., OPA333) | Low‑offset, rail‑to‑rail | | R4 | Sense resistor (laser‑diode current) | 0.1 Ω, 0.5 % | | R5, R6 | Set‑point divider (defines desired diode current) | 10 kΩ (R5) / 1 kΩ (R6) | | C4 | Compensation capacitor | 10 nF | | Q1 | Power MOSFET (N‑channel) | 30 V, 10 A (e.g., IRLZ44N) | | D3 | Flyback diode across Q1 (optional) | 30 V, 5 A Schottky |
How it works:
Illustration placeholder: “Figure 3 – Current‑Regulation Block”