While REV 20 is mature, some manufacturers are moving to digital control (REV 21 with DSP). However, the analog simplicity of the LAE791P REV 20 means it will remain in service for years. A verified schematic ensures maintainability, supporting right-to-repair initiatives and reducing electronic waste.
Slowly ramp AC from 0V to 110V/230V while monitoring:
If all match the LAE791P REV 20 schematic diagram verified values, your copy is accurate.
Critical verification: On REV 20, the gate drive resistor is 22Ω, not 10Ω as in REV 18.
To appreciate the value of verification, one must understand the dangers of unverified diagrams:
The verified schematic diagram for the Compal CSL50 LA-E791P Rev 2.0 motherboard is used in several laptop models, most notably the HP 15-BS series (such as the HP 15-bs526ur) and the Acer Aspire A315-21/A315-21G. Technical Specifications
The LA-E791P Rev 2.0 board typically features the following hardware architecture:
Processor: Sky Lake-U (Intel) or AMD CPU variants depending on the specific model.
Graphics: Integrated or discrete AMD R17M GPU with dedicated DDR3L VRAM. Memory: Supports DDR4 SO-DIMM RAM.
Connectivity: Includes HDMI, SATA, PCIe ports, and USB 2.0 interfaces.
Power Management: Utilizes complex voltage regulation modules (VRM) and standard battery charging circuitry. Verified Download Sources
You can find the verified PDF schematic and related files through the following resources:
Direct Download (Google Drive): A verified PDF copy of the LA-E791P Rev 2.0 schematic is available on Google Drive.
Scribd Archive: Technical overviews and full 34-page documents are hosted on Scribd - LA-E791P Rev 2.0.
Technical Communities: Repositories like ChinaFix provide both the schematic and associated BIOS/EC files for this revision.
Repair Repositories: For professional-grade boardview files and schematics, Laptop-Schematics.com maintains a database entry for the Acer Aspire A315-21 using this board. Repair Context lae791p rev 20 schematic diagram verified
Common issues diagnosed using this schematic include "No display" or "No +VCC_CORE" power rail failures, often linked to SOC or PMIC (Power Management Integrated Circuit) problems.
Do you also need the Boardview file or the BIOS dump for this specific motherboard revision? CSL50 LA-E791P Rev 2.0 Schematic | PDF - Scribd
The LA-E791P Rev 2.0 schematic diagram (also known as the Compal CSL50/CSL52 motherboard used in HP 15-BS series laptops) is available through several specialized engineering and repair repositories. Verified Schematic Resources
You can find the verified schematic and boardview files at the following locations:
Scribd: A comprehensive 55-page LA-E791P Rev 2.0 Schematic Overview is available, detailing the Sky Lake-U system block diagram, power management, and voltage regulation modules.
Schematics Archive (Telegram): The schematics|boardviews| ARCHIVE often hosts verified PDF versions of Compal motherboards for technicians.
Repair Communities: The Laptop Bios & Schematic Facebook Group is a common hub where users share and verify these specific revision files for troubleshooting power issues like +VCC_CORE. Technical Highlights of Rev 2.0
If you are using this for a repair, the Rev 2.0 diagram includes critical sections for:
Power Rail Distribution: Detailed mapping of the DC-in and battery charging circuitry.
CPU/SOC Architecture: Hardware connections for Intel Sky Lake-U processors.
Component Labels: Specific part numbers and signal descriptions for the I/O interfaces and thermal management system. CSL50 LA-E791P Rev 2.0 Schematic | PDF - Scribd
The LA-E791P Rev 2.0 (often referred to under the Compal project name CSL50/CSL52) is a specialized motherboard schematic primarily used for repairing and diagnosing HP 250 G6 and HP 15-BS series laptops. For a technician, a verified schematic like this serves as a definitive blueprint of the system’s electrical architecture, detailing every component from the CPU to individual resistors and capacitors. Hardware Architecture and Components
The Rev 2.0 schematic outlines a robust architecture designed for 6th and 7th Gen Intel Core (Skylake-U/Kaby Lake-U) processors. Key technical highlights include:
GPU Integration: Support for UMA (Integrated) graphics or discrete AMD R17M GPUs with dedicated DDR3L VRAM.
Memory Support: The board is designed for DDR4 SO-DIMM memory, typically featuring one or two onboard slots for system upgrades. While REV 20 is mature, some manufacturers are
Connectivity: Detailed pinouts for essential I/O interfaces, including HDMI, USB 3.0, Ethernet (RJ-45), and SATA for storage drives.
Power Management: Comprehensive sections on the Voltage Regulation Module (VRM), battery charging circuitry, and thermal management systems. The Role of Verified Schematics in Repair
In board-level repair, a "verified" status is critical for ensuring that the diagram accurately matches the physical traces and component values of the motherboard version in hand. CSL50 LA-E791P Rev 2.0 Schematic | PDF - Scribd
LA-E791P Rev 2.0 schematic diagram (also known by the Compal project name
) is a technical document for the motherboard used in laptops like the
This schematic is widely sought for repairs involving power rail issues (such as
) or component identification. Below are the details and verified sources for accessing this specific revision: Motherboard Specifications (Rev 2.0)
The LA-E791P Rev 2.0 motherboard typically includes the following core hardware: Intel Sky Lake-U (integrated SOC). AMD R17M (Discrete Graphics) with DDR3L VRAM. Support for DDR4 SO-DIMM memory. Connections for SATA and PCIe devices. Verified Download Sources
While these documents are proprietary to Compal Electronics, they are frequently hosted on technician forums and document sharing sites: A complete PDF of the CSL50 LA-E791P Rev 2.0 Schematic
is available, though it may require a subscription or account to download. NotebookSchematics: This site often lists LA-E791P boardviews and schematics for professional repair use. Provides specific files for Rev 2.0 BID 08328
, including BIOS and EC firmware which are often needed alongside the schematic for full repairs. Repair Context
Common issues associated with this board revision include "No Display" scenarios caused by SOC or power management problems. If you are troubleshooting a dead board, focus your search on the Power Sequence
page within the schematic to verify if the main rails (3.3V, 5V, and VCC) are initializing correctly. measurement or trying to identify a burnt component on the board? CSL50 LA-E791P Rev 2.0 Schematic | PDF - Scribd
The LA-E791P Rev 2.0 is a motherboard manufactured by Compal Electronics (codenamed CSL50/CSL52) primarily used in the HP 250 G6 and HP 15-BS laptop series. The "verified" status in technical circles refers to schematics and boardview files that have been cross-checked by technicians for accuracy in pin assignments and voltage rail behavior. Technical Overview & Specifications
The Rev 2.0 schematic details a complex Sky Lake-U system architecture designed for mid-range mobile performance. If all match the LAE791P REV 20 schematic
Processor Support: Integrated Intel 6th and 7th Gen Core i3/i5/i7 processors (e.g., i3-6006U, i5-7200U).
Memory Architecture: Supports DDR4 SODIMM RAM with dual-channel interleaved design. Key Integrated Components: Super I/O (EC): ENE KB9022Q D. PWM Controller: ON Semiconductor NCP81218. Audio Codec: RealTek ALC3227. Network: RealTek RTL8111HSH Gigabit Ethernet. Critical Power Rails & Troubleshooting
The schematic defines specific voltage sequences essential for a successful power-on self-test (POST).
Always-On Rails: Outputs of 3.3V and 5V are typically present as soon as power is connected.
Runtime Rails: The 1.8V and 1V rails are "Always On" in some configurations, while others transition to a "Run" state at specific pins (e.g., pin 8 and 9 for 5V). Common Faults:
No +VCC_CORE: Often caused by failures in the CPU power delivery circuit or communication errors with the SOC.
No Power / Dead: Frequently linked to shorts in the U30 power distribution area or charging circuitry.
No Display: Technicians often report "no display" issues that require BIOS/EC firmware reflashing or checking the SOC communication lines. Documentation & Resources
For repair professionals, having both the schematic and the boardview is standard practice for tracing broken traces or identifying burnt components.
If you have the actual schematic file (PDF, EDA project, or exported netlist), you can run most of these checks automatically in your CAD tool; the list also points out manual things to look for.
| Element | Verification Steps |
|---------|--------------------|
| Regulators (linear & switching) | Check input voltage rating, output voltage, and current capability against the load. Ensure VIN is correctly filtered (C‑IN, L‑IN). |
| Decoupling | Every IC pin that requires decoupling must have a capacitor ≤0.1 µF placed as close as possible, plus a bulk capacitor (≥1 µF per 10 mA of load). |
| Inrush & Soft‑Start | If high inrush is expected (e.g., large bulk caps), confirm an NTC or soft‑start circuit is present. |
| Protection | Verify over‑voltage, reverse‑polarity, and over‑current protection (TVS diodes, fuses, PTCs). |
| Battery/Backup | If a backup battery is used, confirm VBAT isolation diode and charge‑control circuit are present. |
Common Pitfall: Missing a ground return for a high‑current regulator (e.g., no GND via or too narrow trace) – flag this for layout.
Most board-level failures originate in power delivery. The schematic shows the input voltage path, DC-DC converters, MOSFET gates, and inductor outputs. For example, if the board does not power on, the technician can follow the 19V input rail through protection circuits to the main regulator (e.g., a SY8288 or similar) and verify each enable signal.
Verification tip: Measure resistance across L and N after the fuse—should be >200kΩ with varistor present.