Bdl51 Lad711p Rev 30 Schematic Work Best

The BDL51 LA-D711P Rev 3.0 is a motherboard manufactured by Compal, commonly found in HP 15-ba series laptops and HP 255 G5 models. Repairing this board requires an understanding of its power sequence, common component failures, and the specific circuit architecture defined in its technical schematic. Technical Overview

Communication interfaces

Part 1: Understanding the Board – BDL51 LAD711P REV 30

1.1 Nomenclature Breakdown

• BDL51: Likely the internal series code for the power supply topology.
• LAD711P: The core driver/controller IC configuration (often related to LED backlight driving).
• REV 30: Revision 3.0. This is critical. Using a schematic for REV 10 or REV 20 may lead to errors, as component values, resistor networks, and even pinouts on connectors can change.

• Fix: Measure the voltage across the current sense resistors (Block D). Compare value to schematic. If voltage exceeds ~1V, the IC trips.

is burnt (common near charging IC), it is a protection diode for the charger IC power supply. You can often harvest this from scrap Compal boards. BIOS Programming: When programming a new BIOS chip, use an 8MB (25B64) bdl51 lad711p rev 30 schematic work

Step 4: 12V or 24V Missing

• Action: Inspect output rectifiers (D609, D610 – Schottky diodes). Check for cracked solder joints.
• Schematic reference: Secondary side – locate the transformer T602 output pins.