Pogo pins power clarification - reading schematics
01-03-2021, 10:22 PM
(This post was last modified: 03-14-2021, 07:28 PM by bokomaru.
Edit Reason: link to old wiki for historical context
)
The wiki seems unclear to me. Wiki - Pogo Pins [edit: link to an old version of the wiki page before changes that were made as a result of this thread. See also the old diagram image ]
There's an image describing the pinout, and there's a breakout board design which seems to match.
Below that, the wiki says
I wonder what "connects to battery voltage" means...
Looking at schematics and datasheets...
I don't see the pogo pins labeled on the physical mainboard. If I put together the component placement drawing (or the pinout on the wiki) with the schematics, I suppose the pinout goes like this.
or
Now...
DCIN: DCIN from J1300 (40PIN) on the mainboard connects to VBUS on J101 (40PIN) on the USB-C small board, which goes to VBUS on J101 (USB_TYPE_C_RECEPTACLE). So DCIN would be the 5V input from a USB-C charger. It goes to ACIN1/ACIN2/VBUS on U600 (AXP803 PMIC). If ACIN/ACIN2/VBUS is available, the AXP803 uses that as the power source and charges the battery. DCIN also goes to pogo PIN1.
USB-5V: PS (IPSOUT? Power Supply?) comes from U600 (AXP803 PMIC) and feeds L606 (LP6226CB6F boost converter), to make USB-5V. USB-5V arrives at pogo PIN5.
DCIN and USB-5V loop: Don't know exactly how this works, but if DRVVBUS is enbled, USB-5V actually provides DCIN through U1302 (LPW5206H USB power loading switch). So we can provide a 5V output for a USB device on the USB-C small board J101 (USB_TYPE_C_RECEPTACLE).
VBAT: In schematics, VBAT comes from J600 (the battery connector). Pretty sure it never touches pogo PIN1/DCIN nor pogo PIN5/USB-5V. The wiki calls pogo PIN1 "VBAT".
Questions:
Reason for asking: Obviously I'd like to use the pogo pins. But we should also clarify the wiki.
There's an image describing the pinout, and there's a breakout board design which seems to match.
Code:
INT SDA SCL
VBUS VBAT GNDBelow that, the wiki says
Quote:The VBUS pin is powered by USB and is 5V at up to 500mA. The second power pin is VBAT, which connects to the battery voltage.
I wonder what "connects to battery voltage" means...
Looking at schematics and datasheets...
I don't see the pogo pins labeled on the physical mainboard. If I put together the component placement drawing (or the pinout on the wiki) with the schematics, I suppose the pinout goes like this.
Code:
PIN6 PIN2 PIN4
PIN5 PIN1 PIN3or
Code:
INT SDA SCL
USB-5V DCIN GNDNow...
DCIN: DCIN from J1300 (40PIN) on the mainboard connects to VBUS on J101 (40PIN) on the USB-C small board, which goes to VBUS on J101 (USB_TYPE_C_RECEPTACLE). So DCIN would be the 5V input from a USB-C charger. It goes to ACIN1/ACIN2/VBUS on U600 (AXP803 PMIC). If ACIN/ACIN2/VBUS is available, the AXP803 uses that as the power source and charges the battery. DCIN also goes to pogo PIN1.
USB-5V: PS (IPSOUT? Power Supply?) comes from U600 (AXP803 PMIC) and feeds L606 (LP6226CB6F boost converter), to make USB-5V. USB-5V arrives at pogo PIN5.
DCIN and USB-5V loop: Don't know exactly how this works, but if DRVVBUS is enbled, USB-5V actually provides DCIN through U1302 (LPW5206H USB power loading switch). So we can provide a 5V output for a USB device on the USB-C small board J101 (USB_TYPE_C_RECEPTACLE).
VBAT: In schematics, VBAT comes from J600 (the battery connector). Pretty sure it never touches pogo PIN1/DCIN nor pogo PIN5/USB-5V. The wiki calls pogo PIN1 "VBAT".
Questions:
- Is that a good read? Did I get it wrong?
- Did I get the pinout right? Why are PIN1 and PIN2 in the middle?
- Does USB-5V/PIN5/VBUS provide a 5V output up to 500 mA?
- Is DCIN/PIN1/VBAT a 5V input for powering the device and charging the battery?
- What happens if you connect a 5V input to DCIN/PIN1/VBAT and to the USB-C connector at the same time? Would that short together two power sources?
- "VBAT, which connects to the battery voltage" would make me think that pogo PIN1 basically connects to the positive battery terminal VBAT. Not true though, right?
Reason for asking: Obviously I'd like to use the pogo pins. But we should also clarify the wiki.
