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I am horribly lost on how to find the value and location of VDD pins in the datasheet found on this webpage. Are there no table of contents for microcontrollers in general?

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  • \$\begingroup\$ In general, yes there is a table of contents in microcontroller datasheets. In fact I can't recall seeing a datasheet which did not have one. The datasheet you link to in your question must definitely did have a table of contents. \$\endgroup\$
    – brhans
    Sep 19, 2023 at 11:22

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In addition to The Photons answer (pin info will typically be on the first few pages, so just scroll down a little) I would like to point out, that the datasheet indeed has a table of contents. And it clearly says "Pin Diagrams" there, which leads you directly to page two: enter image description here

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(In addition to what's been said.)

MCU datasheets usually have a section called 'Electrical Characteristics'. Here you'll find the absolute maximum ratings.

enter image description here

If you search for 'Operating Conditions', you will also find information about the recommended operating conditions. Often they can be found in the chapter 'Electrical Characteristics'. In this datasheet they are in the chapter 'DC AND AC CHARACTERISTICS GRAPHS AND TABLES'.

enter image description here

Source: PIC16F87XA datasheet


Why they don't they have a typical value for VDD?

That's because any value between (inclusive) VDD,Min and VDD,Max (recommended operating conditions) is equally valid.

But if you insist: the typical values are 3.3 V and 5 V

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  • \$\begingroup\$ Thanks so much! :) Although I am curious why they don't have a typical value for VDD? \$\endgroup\$
    – Seth Shill
    Sep 19, 2023 at 14:41
  • \$\begingroup\$ The typical values are 3.3V and 5V. \$\endgroup\$
    – Velvet
    Sep 19, 2023 at 14:47
  • \$\begingroup\$ I mean typ in the chart is left blank. I want to know cuz I'm powering a device that takes 3.3v :) \$\endgroup\$
    – Seth Shill
    Sep 20, 2023 at 3:52
  • \$\begingroup\$ Yes, I know it's left blank. Because any value in the range 2.0V .. 5.5V is valid. But in the industry the typical values you'll find are 3.3V and 5.0V. \$\endgroup\$
    – Velvet
    Sep 20, 2023 at 5:22
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The pin assignments are shown starting on page 2 of the datasheet. For the 28-pin QFN, for example, they give this diagram: enter image description here

VDD is clearly marked on pin 17.

If you prefer to have the information in tabular form, the pin assignment tables start on page 8 or 10 (depending which part number you want). You just have to scan through to find the line for VDD and the column for your package type.

The Table of Contents is on page 4: enter image description here

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    \$\begingroup\$ This tells what the OP is looking for, but the question asks how to find it. And, it can be found by using the search feature of the PDF reader, e.g. Ctrl-F and type in "VDD" and that's how these are found. \$\endgroup\$
    – Justme
    Sep 19, 2023 at 5:27
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    \$\begingroup\$ @Justme, I found it by opening the PDF and hitting PageDn a couple of times until the pin diagrams appeared. If I'm looking for the description of some register that's going to be in the middle of the document I'll go to Ctrl-F, but for something that's going to be in the first few pages? Just scroll until it shows up. \$\endgroup\$
    – The Photon
    Sep 19, 2023 at 5:31
  • \$\begingroup\$ That may work if you already know it will be on the first few pages, which a person opening the data sheet for the first time would not know. And for other MCUs, the register map can be in a separate reference manual, so you would have to already know that as well. For example there have been questions like "Where in the datasheet is STM32 register map, I can't find it" and it's not in the datasheet. \$\endgroup\$
    – Justme
    Sep 19, 2023 at 10:23
  • \$\begingroup\$ @Justme, ultimately you have to just read a few dozen datasheets (from the vendors you favor), and you learn roughly where to find things like that. \$\endgroup\$
    – The Photon
    Sep 19, 2023 at 14:20

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