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I am using an LDO to convert a 5V rail to 3.3V for a microcontroller. I am using the TLV707 from Texas Instruments.

It gives a recommended schematic as shown here:

LDO Typical app circuit

and I have used this. I have used 1uF for both the input and output capacitors.

However just below this in the datasheet, it states the input is 1.8V-3.6V and output is 1.2V and 100mA.

The datasheet and website both state that the component can have an input of 5.5-6V and output up to 3.6V and 200mA.

LDO Product details on TI website

How do I configure the device to allow an input of 5V and output of 3.6V? The datasheet says nothing about adding additional components to feedback and control the device.

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  • \$\begingroup\$ A bit of advice. Always read the datasheet through twice, carefully before asking questions. It is embarrassing to ask a question that is answered in the datasheet. Also, sites like digikey and mouser can be very helpful for sorting out exact part numbers. \$\endgroup\$
    – user57037
    Sep 22, 2021 at 17:26
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    \$\begingroup\$ Do you want 3.3 V like you say in the first sentence or 3.6 V like you say in the last sentence? \$\endgroup\$
    – user57037
    Sep 22, 2021 at 17:27

4 Answers 4

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If you look in the 'Ordering Information' section of the datasheet, it tells you what you are looking for (page 26 of the datasheet):

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Using that, you can find your part number. From Digikey, you find what you are looking for

enter image description here

So your part number would start with TLV70736. The remaining characters give you packaging information, as described in the Ordering Information section, as well as a Packaging Information section later in the datasheet.

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It does not have external feedback you can configure. You must buy a specific part number which determines the output voltage with internal feedback.

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  • \$\begingroup\$ How can I know the exact part number which provides the input and output conditions I require when the datasheet does not have a page which says LDO PartNo xyz has an input of XV and an output of YV? \$\endgroup\$
    – MRB
    Sep 22, 2021 at 17:15
  • \$\begingroup\$ The datasheet does have a page which says how the part numbering works. The input conditions will depend on output voltage (and current) so that won't be in the part number. Input voltage must be somewhat higher than your selected output voltage, but input voltage can't be higher than 5V. \$\endgroup\$
    – Justme
    Sep 22, 2021 at 18:15
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In the datasheet, there is a Package Option Addendum beginning on page 28. The part numbers listed include the output voltage. For example the first part is TLV707085DQNR, where 085 refers to the output voltage 0.85V. You can decide from here which part you need since there are several with 3.3V outputs and variable other parameters.

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You order a TLV70733 -- note the "33" at the end of the part number. These are fixed voltage regulators. If they were designed so that the user could set them up for a specific voltage, they'd have "adjustable" or "programmable" in the name.

(Edit: I had said "36" originally, because I misread your question.)

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