I've been trying to get a fixed output LDO to work for the past few hours, in order to step 3.6 V down to 3.3 V, but I have been unsuccessful. I am using the MCP1824T-3302E/OT LDO.

I have it wired up very similarly to the diagram on the third page. I am using a 3.6 V Li-po battery and I have its voltage and ground connected to VIN and GND(TAB), I have a 1 µF capacitor connected between VIN and GND(TAB) (the sample diagram uses a 4.7 µF capacitor, but later in the documentation it says anything between 1 and 10 µF is fine and I am out of 4.7 µF capacitors at the moment), I have SHDN wired to the input voltage, and I am using a 1 µF capacitor as the output capacitor. I'm pretty sure that I have every component that I need attached, but my multimeter reads nothing from the VOUT pin no matter what.

If it matters, these are the kind of capacitors I'm using.

Does anyone have any idea what I could be doing wrong?

Here is a picture of my setup:

enter image description here

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    \$\begingroup\$ Time for a photo of your layout? \$\endgroup\$ – Transistor Jul 20 '16 at 19:25
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    \$\begingroup\$ The cold-joint issues mentioned by @jbord39 can (mostly) be verified by measuring on the actual pins on the component, apart from intermittent issues and overheating. \$\endgroup\$ – pipe Jul 20 '16 at 20:42
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    \$\begingroup\$ What Jbord39 said, plus those caps are too far from the IC. Plus no load (add a 10 mA led + resistor setup). That said, you should still see a voltage out unless you have a bad solder connection or damaged the IC. Check for continuity on all pins and wires, with the battery off. Or get a proper breakout board. \$\endgroup\$ – Passerby Jul 20 '16 at 20:43
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    \$\begingroup\$ Looks like there is about 6-10 inches of wire between the IC and the capacitors. That can be a problem, as the long wires have series inductance. The capacitors won't be effective as bypass capacitors, unless they are close to the IC pins. \$\endgroup\$ – MarkU Jul 20 '16 at 20:43
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    \$\begingroup\$ @R_Misra I'm glad you're following the advice given by the commenters, a lot of askers start to argue instead. This increases both your chances of solving the problem, and of getting more helpful answers. \$\endgroup\$ – pipe Jul 20 '16 at 22:04

I see 3 possible sources of the problem:

1 - Cold solder joints (little soldering experience)

2 - IC damaged

3 - No load resistor

  • \$\begingroup\$ Already tested for cold solder joints. I was just testing for an output by measuring the voltage between Vout and ground- do you mean that I would have to put a resistor between Vout and ground in order to get an output in the first place? John said "it is good to have a load so that the output doesn't have to be discharged backwards through the part at power down"- is this what you mean? \$\endgroup\$ – Tri Jul 26 '16 at 15:21

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