Each phase pair (U+/U-, V+/V-, W+/W-) goes through a series of protection diodes and then directly to the spindle motor connector. Use a multimeter in continuity mode to map which pin corresponds to which motor winding.
Pins 5 and 6 connect to a small ceramic capacitor (typically 0.47µF to 1µF, rated >16V). If this capacitor is shorted or low capacitance, the high-side MOSFETs will not turn on properly, causing the motor to twitch but not spin.
Let’s walk through a real 17IPS72 schematic work scenario.
Symptom: External USB hard drive spins up, then clicks three times and spins down.
Diagnosis:
Lesson: A 10-cent capacitor saved a $1000 data recovery job. 17ips72 schematic work
Based on the phrasing, "17ips72" almost certainly refers to the LG 17IPS72 power supply board, which is commonly found in LG ultrawide monitors (such as the 34UC79G or similar models). These boards are frequent subjects of "schematic work" threads on electronics repair forums like BadCaps and YouTube.
Here is a review of the "work" typically associated with this specific board, analyzing why it is a popular subject for repair technicians and DIY enthusiasts.
Let’s be honest: finding a clean, readable schematic for the Lenovo Legion Y720-17IKB (motherboard model 17IPS72 or NM-B191) feels like hunting for a ghost.
For the uninitiated, the alphanumeric code 17ips72 isn't just random chassis jargon. It is the key to unlocking board-level repair on this popular (but aging) gaming laptop. Whether you are battling a “no power” condition, a shorted CPU rail, or the infamous Legion USB-C port failure, you need the roadmap.
Here is everything you need to know about the 17IPS72 schematic—what it contains, where to find it legally, and how to use it without frying your board. Each phase pair (U+/U-, V+/V-, W+/W-) goes through
Project Title: Schematic Reconstruction and Circuit Analysis of the 17ips72 Mainboard Date: October 26, 2023 Subject: PCB Model 17ips72 (17-inch Integrated Power Supply)
Let’s run a real diagnostic using the schematic and boardview.
Step 0: Remove all peripherals, RAM, SSD. Connect DC supply at 19V/3A.
Step 1: Measure +PWR_SRC at the drain of the first isolation MOSFET (PQ102). Schematic Ref: Page 6, label "CHARGER INPUT."
Step 2: Measure +3VALW at C2302 (near the PCH). If 0V, go to Page 4 (Power tree). See +3VALW is made by PU201. Check Pin 7 (VIN) = 19V. Pin 6 (EN0) = 3.3V. If EN0 is missing, trace back to PWR_SRC_DIV through resistors PR213/PR214. Let’s walk through a real 17IPS72 schematic work
Step 3: Assuming 3.3V and 5V are present, press the power button. Does PWRBTN#_EC toggle? Probe pin 36 of the EC (IT8226VG). No toggle? Bad power button board (check connector JEC1 using boardview).
Step 4: If toggle is good, measure SUSP#. Probe Pin 99 of the EC. Should go from 0V to 3.3V. If it stays 0V, the EC is dead or its firmware is corrupt (requires reballing or replacement with pre-programmed EC).
Step 5: Next, check EC_RST# (EC Reset). Pin 102 of EC. Must be 3.3V constantly. If it pulses or is 0V, the +3VLP rail is unstable or the reset capacitor (C8802) is leaky.
Step 6: Finally, check PLT_RST# (Platform Reset) at PCH pin J12 (or the BIOS chip pin 6). This is the final master reset. 0V means the PCH never received all power-good signals. Use the schematic to trace back SYS_PWROK and PCH_PWROK.