What is the ripple in millivolts of U3V12F12 when supplied with 5v (usb) ?
We have not characterized the output voltage ripple of our regulators. In general, it will depend on lots of factors in your system, like the load, wire lengths, and amount of noise on the input, so it is best to test it in your particular setup. Do you have a specific reason for concern about the amount output ripple?
By the way, this particular regulator needs up to 2A at start up, so supplying it from USB might limit the input current too much for it to ever turn on properly.
I am trying to power a Phono Preamplifier (6 to 15v, 3 mA) from a 5V USB adapter (that also powers a Dayton Audio WFA02 WI-FI streaming unit). From you description, U3V12F12 does not sound like the best step up voltage regulator for this. Is there any alternatives that can run better with this very low current ?
I tested a few of our other step-up and step-up/step-down regulators and saw large start-up current draws on all of them, so we can’t guarantee any of them will work with a supply that has a low current limit, but I also tested all of them (including the U3V12F12 regulator) with power from a computer USB port and they all reliably turned on every time. So the U3V12F12 might work just fine in your system; it will depend on the details of your particular USB port.
Also, to be clear, the high current draw is just a very short inrush (few ms) on startup. After that the quiescent current of that regulator is below 2mA.
Thank you Claire. Any suggestions for a simple input spike and output ripple filter ?
Adding capacitors to the input and output would probably help both of those, but beyond that we do not have any specific recommendations for specific values or filter types.