Laptop: Lenovo YOGA 3 Pro-1370
Board: NM-A321
Schematics attached, Page: 30 Question: The BQ24770 is a Battery charger IC. It’s pin #5. I’m not getting ACOK signal. ACOK signal will generate +3VALW on power which is missing.
As per BQ24770, datasheet attached, Pin #5. For this to be on the following criteria needs to be met: ACDET above 2.4 V: This is correct and board is good with this value.
VCC above UVLO but below ACOV: This is what I’m unsure about, where do I find UVLO? It’s not on schematics, from Googling it means, undervoltage lockout (UVLO) function to disable the device at low supply voltages. From this I gather it’s the ENABLE signal needs to be ENABLE, but I don’t know where this is and how can I find It on schematics.
VCC above BAT: This is also correct, when there is no Battery is present, it’s 0V, I gather this should be OK unless I’m wrong.
Can someone please help me understand the UVLO and how I can measure it?
I have also used 2 original Lenovo chargers, 1 compatible and for the original Lenovo chargers, their cables are removable, 3 cables altogether I've tried.
All had 20V supplied to the system. Battery would not charge as well and the issue is same with or without battery plugged in.
Thank You!
[MOD EDIT} Link to schematic & Boardview -> https://www.badcaps.net/forum/troubl...0-lcfc-nm-a321
Board: NM-A321
Schematics attached, Page: 30 Question: The BQ24770 is a Battery charger IC. It’s pin #5. I’m not getting ACOK signal. ACOK signal will generate +3VALW on power which is missing.
As per BQ24770, datasheet attached, Pin #5. For this to be on the following criteria needs to be met: ACDET above 2.4 V: This is correct and board is good with this value.
VCC above UVLO but below ACOV: This is what I’m unsure about, where do I find UVLO? It’s not on schematics, from Googling it means, undervoltage lockout (UVLO) function to disable the device at low supply voltages. From this I gather it’s the ENABLE signal needs to be ENABLE, but I don’t know where this is and how can I find It on schematics.
VCC above BAT: This is also correct, when there is no Battery is present, it’s 0V, I gather this should be OK unless I’m wrong.
Can someone please help me understand the UVLO and how I can measure it?
I have also used 2 original Lenovo chargers, 1 compatible and for the original Lenovo chargers, their cables are removable, 3 cables altogether I've tried.
All had 20V supplied to the system. Battery would not charge as well and the issue is same with or without battery plugged in.
Thank You!
[MOD EDIT} Link to schematic & Boardview -> https://www.badcaps.net/forum/troubl...0-lcfc-nm-a321
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