Hey all,
I'm looking for a little advice. I found an old Apple iPod HiFi at a thrift store for cheap and I'm looking to remove the ancient 30pin FW connector and install a small piCorePlayer+DAC inside the box.
The stock HiFi power supply outputs the following:
+17V (1.6A)
+6V (0.3A)
+3.3V (0.1A)
The +17V current drops to 0.5A when using 7.5-9.9V (5A) DC input (aka D-cell batteries) but I don't ever envision using this.
The RPi Zero W requires 5V and about 200mA.
I don't have a scope but I imagine the stock DC is quite clean. In the past I've used a cheap switch mode power supply but, being audio, I worry that these will be too noisy without me designing suppression (shudder... zener, inductors and capacitors and shielding). Did I mention I don't have a scope at home? I doubt I'm the first two encounter this issue and, before I dust off textbooks and think hard about it, I figured I'd post and ask if anyone knows of an off-the-shelf board or design suitable for cleanly knocking down the 17V line?
Results 1 to 7 of 7
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2019-01-25, 08:14 #1
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piCorePlayer in a 2005 Apple iPod HiFi
Last edited by rdb; 2019-01-25 at 08:40. Reason: spelling
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2019-01-25, 08:30 #2
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Are you referring to one of the big boxes with built-in speakers.
https://en.wikipedia.org/wiki/IPod_Hi-Fi
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2019-01-25, 08:32 #3
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2019-01-25, 08:36 #4
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My first thought was to find is a SMPS that brings the 17V down to ~6V and then a low-noise linear regulator to bring that down to +5V. Of course, it needs to be small and it cannot overheat.
Last edited by rdb; 2019-01-25 at 08:39.
Randy
2xBoom, 3xRadio, 1xDuet, 1xSoundbridge
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2019-01-25, 08:56 #5
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This might help
https://harmlesssaucer.wordpress.com...-raspberry-pi/
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2019-01-25, 09:06 #6
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- Jan 2016
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Thanks. They actually just tapped the input AC and added an Apple USB power supply (A1385) in line to power the RPi. Another option.
Every mod I've seen thus far leaves the existing 30pin dock. I'd rather remove it and tap into the audio pins on the dock connector, leaving the aux 3.5 jack alone. I'm contemplating using this space for an OLED screen.Last edited by rdb; 2019-01-25 at 09:12.
Randy
2xBoom, 3xRadio, 1xDuet, 1xSoundbridge
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2019-01-30, 21:03 #7
Not to shift the thread, but I attached a bluetooth receiver to my iPod HiFi and send from my phone. Sounds fantastic! The iPod HiFi can get very loud without distorting and for what it is has a pretty good soundstage if you are situated just right.