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ap7313 voltage regulator on audio board
there is a ap7313 voltage regulator on the audio board. what is it for?
It draws from my teensy 3.2's 3.3v (max 250ma). i hope to use this 3.3v for other things (xbees). what current should i expect the audio portion is using?
Hi, this is the schematic:
And this is the datasheet:
The SGTL5000 requires 1.8V power for its internal digital logic circuitry.
Originally Posted by mpinner
That depends on whether you use a SD card and/or headphones at high volume.
what current should i expect the audio portion is using?
As a quick check, I just programmed a Teensy 3.2 with File > Examples > Audio > Synthesis > Guitar, using 96 MHz and all the default settings. Here's some quick current measurements, done by powering the board from a 5V lab bench power supply and reading the current right from the power supply's display (reasonable, but not as accurate as going to the trouble of connecting a multimeter inline).
40 mA, Just running without any audio shield at all
56 mA, with the audio shield, no SD card, no headphones
56 mA, with the audio shield, no SD card, with Bose headphones
58 mA, with the audio shield, with Sansung 32GB SD card (unused), with Bose headphones
To check how much the SD card uses, I reprogrammed it with File > Examples > Audio > WavFilePlayer
61 mA, with the audio shield, with Sansung 32GB SD card, with Bose headphones, default (0.5) volume
65-91 mA, with the audio shield, with Sansung 32GB SD card, with Bose headphones, max (0.8) volume
The current probably peaks higher than 91 mA in this last test. I just powered the whole thing from VIN & GND and watched the numbers on my power supply's fairly slow display.