WELCOMES YOU!!
Always-on power rail for USB controllers and primary system standby. Dedicated power rail for DDR4 memory modules. +1.0V_PCH Standby and operational core voltage for the PCH core. +VCC_CORE Variable (~0.8V - 1.2V) CPU Core power infrastructure, managed by multi-phase PWM. 3. Power-On Sequencing and Diagnosis
This public link is valid for 7 days and shares a thread, including any personal information you added. This link or copies made by others cannot be deleted. If you share with third parties, their policies apply. Can’t copy the link right now. Try again later.
Since this board charges via USB-C, the PD Controller (often a TPS series chip) frequently fails. The schematic helps identify the CC1/CC2 lines and the 20V input rail.
Let’s decode a snippet. On the LA-E801P Rev 2.0, look for the rail (DDR3 memory power). la-e801p rev 2.0 schematic
: Supports Intel Kaby Lake-U processors.
If the fan spins but there is no display, check for the CPU_VR_READY signal on the schematic. Technical Specifications for the LA-E801P Rev 2.0 Platform: Intel Kaby Lake-U Memory: LPDDR3 (Integrated on-board) GPU: Integrated Intel HD Graphics IO: USB Type-C / Thunderbolt support Tips for Effective Troubleshooting
Symptom 2: Power Blue LED Turns On, Then Turns Off Immediately Always-on power rail for USB controllers and primary
: Often fails at the first input MOSFET. If 19V enters but doesn't pass the first stage, check the gate voltage and surrounding resistors.
Input MOSFETs (usually dual N-channel MOSFETs configured as reverse-polarity and over-voltage protection), current sensing resistor ( PR302 or similar depending on exact schematic notations).
Deep Dive: Analyzing the LA-E801P Rev 2.0 Schematic – A Repairman’s Perspective +VCC_CORE Variable (~0
Compal LA-E801P Rev 2.0 (also known by codenames ) is a motherboard found in the series and laptops. This board typically supports Intel 6th (Skylake-U) 7th (Kaby Lake-U) Generation processors and features discrete AMD Radeon graphics or integrated Intel graphics. HP Support Community Core Technical Specifications : Intel Kaby Lake/Skylake-U 15W. : Dual-channel DDR4-2133MHz SO-DIMM, operating at 1.2V. : Options include integrated Intel HD Graphics or discrete AMD Radeon R5/R7 : SATA interface and support for M.2 SSDs (PCIe/SATA). Networking
The EC passes this signal to the PCH/SoC via PBTN_OUT# . The PCH responds by releasing sleep state signals ( PM_SLP_S5# , PM_SLP_S4# , PM_SLP_S3# ).
+3VALW : Powers the Embedded Controller ( KB9022Q ) and the main BIOS chip ( U22 ). +5VALW : Powers secondary sensor circuits and standby rails.