questions on a schematic

[redgear]

The above schematic shows pin 24(VSP) as shorted with pin 23(VSYS4) and pin 22(VSYS3). Is that correct?
In the other side, only capacitor CP12 is shown as a polarized capacitor but the other capacitors also seem to use the naming convention as a polarized capacitor(CPxx). Is that a mistake or all capacitors polarized?

Thanks

[PA0PBZ]

(Attachment Link)

The above schematic shows pin 24(VSP) as shorted with pin 23(VSYS4) and pin 22(VSYS3). Is that correct?

No, they are just crossing on the diagram.

In the other side, only capacitor CP12 is shown as a polarized capacitor but the other capacitors also seem to use the naming convention as a polarized capacitor(CPxx). Is that a mistake or all capacitors polarized?

They should all be polarized.

[magic]

The above schematic shows pin 24(VSP) as shorted with pin 23(VSYS4) and pin 22(VSYS3). Is that correct?

By usual convention, if there is no dot where the lines intersect, they aren't connected. Although it doesn't preclude mistakes or people trying to be creative.
I would say that VSN and VSP are each connected only to one capacitor and VSYS3 and VSYS4 are separate too.
What is this device supposed to be and do?

In the other side, only capacitor CP12 is shown as a polarized capacitor but the other capacitors also seem to use the naming convention as a polarized capacitor(CPxx). Is that a mistake or all capacitors polarized?

Perhaps a mistake, perhaps they meant an MLCC. I'm not sure what's the state of the art but 22µF/25V isn't far from values I know are possible.

[redgear]

No, they are just crossing on the diagram.
They should all be polarized.

Thanks...
There are more capacitors with a unpolarized symbol having the name CPxx. Should they all be polarized? I am attaching the entire circuit below.

By usual convention, if there is no dot where the lines intersect, they aren't connected. Although it doesn't preclude mistakes or people trying to be creative.
I would say that VSN and VSP are each connected only to one capacitor and VSYS3 and VSYS4 are separate too.
What is this device supposed to be and do?

This a Powerbank SOC. It identifies and controls the fast charging protocols. The name of the IC is IP5328P

[JackJones]

It isn't very clearly drawn, but there is another example schematic right at the top of the datasheet. On that it seems all the VSYS pins and VSP are connected together.

The VSYS pins are commoned in the example you posted as well, they are just using a global label to do so. So not very clearly drawn again.

[PA0PBZ]

In the datasheet they say that CP4,5,6 and 11 are "chip capacitors" and CP12 is an "electrolytic capacitor, so maybe MLCC after all although electrolytic would do a fine job there too in my opinion.

[redgear]

It isn't very clearly drawn, but there is another example schematic right at the top of the datasheet. On that it seems all the VSYS pins and VSP are connected together.

The VSYS pins are commoned in the example you posted as well, they are just using a global label to do so. So not very clearly drawn again.

Just checked the diagram on top of the datasheet. What can I do? Should I connect them together?

In the datasheet they say that CP4,5,6 and 11 are "chip capacitors" and CP12 is an "electrolytic capacitor, so maybe MLCC after all although electrolytic would do a fine job there too in my opinion.

Thanks... Will use a electrolytic cap there.
I'm confused about the other connections.

[JackJones]

Actually, there is a layout picture of that specific area. It does show that pins 22, 23 and 24 are indeed connected together.

[iMo]

All that capacitors are part of the Boost converter together with L1=2.2uH (based on the schematics in DS). So rather small ESR there is required, therefore many in parallel.
I would rather stay with 22uF MLCC there.

[PA0PBZ]

Actually, there is a layout picture of that specific area. It does show that pins 22, 23 and 24 are indeed connected together.

Yes, I stand corrected, this is one of the worst drawn schematics I've ever seen, you should never cross connections like that if they are connected but do something like this:

Code: [Select]


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[JackJones]

Combine that with different thickness used for the traces it is definitely confusing. (though I like the idea of identifying high current traces like that) If there was a dot to mark a connection it would be much clearer.

They even used the exact replica of the pinout of the chip to make the schematic, rather than arranging it nicely to make it clear. Compare it with the example schematic at the top of the datasheet where everything is arranged neatly and is easy to read.

[redgear]

Thank You everyone. I will post the schematic once I complete it. Would be great if you guys can review it.

[soldar]

For schematics I like a blob of Sn solder if they are connected and a sort of "shadow" if they are not connected. I think this avoids confusion.

If it is not a crossing but just a T then there is no doubt they are connected.

[redgear]

I'm attaching the schematic I created and the datasheet. Can someone please review it?


1) The IP5328P is a custom symbol created by me, when I connect a Label to the pins it creates a junction but no junction is created for single connection on pins in the USB ports(kicad default symbols). Did I make a mistake while creating the symbol?
2) I hope the Gate, Drain and Source pins of the MOSFETs are properly connected.
3) They have used a Electrolytic Cap for C15. Can I use the same? Will any SMD cap should be fine for others?
4) The pins VSYS,VSN and VSP are connected together. I have tried to follow the the diagram on top of the datasheet, have I done that correct?

[redgear]

Do I really need a 220uF 25v capacitor on the C15? Many powerbanks using the IP5328P does not use any Electrolytic cap at all and the ones that use have them rated at 100uF 16V.

http://bbs.chongdiantou.com/data/attachment/forum/201909/29/095355uyh41te7nfpvyh1x.jpg

http://bbs.chongdiantou.com/data/attachment/forum/201811/08/180416m6kzrpcb8mp43i49.jpg

http://bbs.chongdiantou.com/data/attachment/forum/201910/15/141137n02444z4lvr97mk3.jpg

http://bbs.chongdiantou.com/data/attachment/forum/201901/09/220736y17r7c7c9ts7z3l3.jpg

This one uses a 220uF 16v capacitor:
http://bbs.chongdiantou.com/data/attachment/forum/201909/03/112541yz4auqu4ohzav494.jpg