TINA/Spice/TPS563208: Having trouble understanding the schematic/layout of this part due to inconsistencies.

Ryhan Chowdhury57

Part Number: TPS563208
Other Parts Discussed in Thread: TINA-TI

Tool/software: TINA-TI or Spice Models

I am running into several issues with this part. I am trying to step down a 7.4 V input to a 5.5 V output. I successfully got that output using the TINA TI macro for the part with the following schematic:

Vout7 is the output i want which is 5.5 V:

However I am running into issues with the wiring. The schematic provided on the datasheet is not identical to the one on TINA which makes it very confusing to wire since on TINA it has 2 pins on the left side and 4 on the right and they're all completely out rearranged whereas on the datasheet it looks like this:

In addition, there isn't a circle on the top left corner of the IC itself to indicate the correct orientation, so for all I know, it could be upside down:

Please let me know if there's anyway you can clarify this. I am also confused why there are two output voltages on the datasheet schematic.

Thanks!

over 8 years ago

0 Andy Chen over 8 years ago

TI__Mastermind 34875 points

Hi,

You just need to follow up the Pin name no matter how the symbol is drawn in TINA , Webench, Altium circuit or on data sheet. TINA macro model symbol was no t designed same as actual package pin-out.

0 Ryhan Chowdhury57 over 8 years ago in reply to Andy Chen

Prodigy 100 points

What do you mean "follow up the pin name"? Also, why is there to output voltages on the datasheet?

0 Aaron Jones over 8 years ago in reply to Ryhan Chowdhury57

TI__Intellectual 760 points

Hi Ryhan,

The output voltages on the datasheet are "Net ties". Vout on the left is the output voltage, Vout on the right shows that output voltage being resistor divided down and fed into the IC.

I agree that it's slightly confusing, but those are the same net, just symbolically tied together to make the wires cleaner. If the datasheet were redrawn, it would take the same form as Tina.

The layout might make this easier to read:

0 Ryhan Chowdhury57 over 8 years ago in reply to Aaron Jones

Prodigy 100 points

So when I'm breadboarding this, should I try to make it identical to the schematic on TINA? If so, I am still slightly confused because there isn't a circle on the IC to indicate the correct orientation, and on top of that, the TINA schematic has 2 pins on the left and 4 pins on the right where the actual IC has 3 on each side. Is there a way to address this?

0 Aaron Jones over 8 years ago in reply to Ryhan Chowdhury57

TI__Intellectual 760 points

Page three of the datasheet shows physical layout of pins. Schematic symbol does not necessarily reflect physical chip. The IC should have a marker for pin 1.

0 Ryhan Chowdhury57 over 8 years ago in reply to Aaron Jones

Prodigy 100 points

I did not see a mark anywhere on the chip, but I'll be sure to look again in a bit. As for the how I should wire the chip, should I wire the passive elements identically to how I have the TINA schematic while noting the correct layout shown on page 3?

0 Aaron Jones over 8 years ago in reply to Ryhan Chowdhury57

TI__Intellectual 760 points

yes

0 Ryhan Chowdhury57 over 7 years ago in reply to Aaron Jones

Prodigy 100 points

Aaron,

I took a very clear picture of the chip, and I don't see a dot anywhere on it that indicates how the pin is supposed to be oriented. Is there a way to address this?

Power management

Power management forum

TINA/Spice/TPS563208: Having trouble understanding the schematic/layout of this part due to inconsistencies.