Off-Topic > Off-Topic - Tiny Core Lounge
Raspberry Pi
Rich:
Hi spence91
From the link you provided:
--- Quote ---The board takes fixed 5V input,
--- End quote ---
Nowhere does it state (that I could find) you can run from 16V. Read this: http://www.raspberrypi.org/archives/260
Also from the link you provided:
--- Quote ---This permits adoption of the micro USB form factor, which, in turn, prevents the user from inadvertently plugging in out-of-range power inputs; that would be dangerous, since the 5V would go straight to HDMI and output USB ports, even though the problem should be mitigated by some protections applied to the input power: The board provides a polarity protection diode, a voltage clamp, and a self-resetting semiconductor fuse.
--- End quote ---
I took a look at the schematic for the model B, the link for the PDF can be found here: http://www.raspberrypi.org/archives/1090
Here's what I saw for the power supply input:
1. A series connected semiconductor fuse rated for 1.1A at 6V, followed by
2. A shunt connect 5V bi-directional transzorb
3. NO POLARITY PROTECTION DIODE
As you increase the input voltage above 5V, the transorb will begin conducting current and clamp the voltage to the board
at 5V. This excess current will heat up the fuse until you reach about 1.1A, at which point it's resistance suddenly becomes
very high and shuts down the board. Once it cools down, it's resistance once again drops. The purpose of this circuit is to
clamp momentary spikes and surges, not to serve as a mechanism to regulate higher voltages to 5V. If you do actually
apply a solid 16V supply, the transorb will have 5V across it, leaving 11V across the 6V fuse, most likely destroying it.
spence91:
Rich - my bad, the 16V came from the C6 capacitor that's on the board (I skimmed the article) that aids with DC regulation.
--EDIT--
Also here's a list of Verified power sources - many of them phone chargers.
http://elinux.org/RPi_VerifiedPeripherals#Power_adapters
Rich:
Hi spence91
I suspected it was something like that.
@ALL: You want to use a 5 volt 1 amp REGULATED power supply.
cast-fish:
--- Quote from: bmarkus on August 06, 2012, 04:16:38 PM ---A phone charger is not a power supply.
--- End quote ---
You do talk some Rubbish sometimes.
It's like. "did he even read the sentence before posting it?"
Ofcourse a phone charger is a "power supply" because it powers the phone
while charging the phones empty battery.
What school did you go to?
V.
bmarkus:
--- Quote from: cast-fish on August 14, 2012, 10:44:03 PM ---
--- Quote from: bmarkus on August 06, 2012, 04:16:38 PM ---A phone charger is not a power supply.
--- End quote ---
You do talk some Rubbish sometimes.
It's like. "did he even read the sentence before posting it?"
Ofcourse a phone charger is a "power supply" because it powers the phone
while charging the phones empty battery.
What school did you go to?
V.
--- End quote ---
Thanks. School? M.Sc.E.E in electronics and computer sciences, amateur radio operator with HAREC licence. To be honest I'm tired to discuss hw construction details whith someone who knows nothing about circuits and takes out one sentence without reading deatails.
You can do whatever you want with your toys. Please, let me out of your bussiness.
Thanks.
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