Search results

With regular USB (labelled as USB) there is 100mA or 500mA current limit. With microUSB phones, there was a "charge mode" added, identified by a resistors between D+ and D- and/or GND and/or VBus, which has a limit set by the device's manufacturer, as you are to use the manufacturer's PSU. Apple...

Plastic-enclosed SBCs always rely on connectors as heat sinks, because they allow radiation as well as natural convection of heat to the outside without heating the well-insulated case. The most important thing for that to work is the thermal bond between the SoC and the connectors, which is...

It was increased from planned 8 to actual 10 for the first prototype, because routing was more complex than expected. But seems like The other 2L were added because of the supply problems, totally forgot about those. Sadly, lots of people use this as a reference nowadays, but If I (or you)...

Not all companies make µVias with laser :P (Yes, there are drills that thin!) Anyway, either they have to throw half of the PCBs into the trash after inspection (price x2) or they use machines (and drills) twice as expansive (machine time*cost x2 = price x2).

I don't get it either. Afaik set-up is less than ~ USD 50 per layer in china, so 500 USD max. Plus ~ USD 100 for e-test adapter. And production is less than USD1 per layer for 1/2euro card (80x100), standard design rules, standard production time, if you fill the production panel. For other...

For typical boost designs, the peak efficiency is between 80% and 90% -> 2.3A. What's the max. output current of the USB connector/battery/charger? WD Red, which I'd prefer and recommend, need 0A@5V + 0.28..0.53A@12V (depending on size) during write. The peak current of 1.2-1.8A might be a...

That's why I/we used the term "Desktop HDD" (which are 3.5").

Yes, but there is no way to directly power it from the pyra. There were some housings with eSATA + external PSU, no idea if they still exist.

Nope. External housings have a step-up converter to generate 12VDC from VBus (5VDC). Almost all (normal) Desktop SATA HDDs have the rotor connected to 12VDC and the logic connected to 5VDC. Afaik, eSATAp drives may be powered from 5VDC, so the cable shown above on page 1 *may* work for eSATAp...

I'd route audio through USB or HDMI. I guess he means something like the DELL docking stations which use an additional connector at the bottom instead of the back-side connectors. It has additional ports on it (like SATA for CD drive).

My guess is that the dock would need 2 male connectors plugged at once: USB (Power, HUB [, SATA]) and HDMI. Afaik, the 1.5GHz is the maximum (regardless of voltage), so you could only switch/disable the power governor (to reduce "lag" on load-switching) and keep it cool to ensure the CPU won't...

Probably because it would break the "brick" form factor (you can't grab AND use it with one hand, if it's too thick). That's why I'd love to use the pyra as a phone-replacement (probably with a (wireless) headset). Obviously, these connectors make no sense for a phone, but they do not matter for...

Talking about multi-layer and design-times, wouldn't it be easier to just not populate the parts that are not required? Sounds awesome. Do you have any ideas about pricing? The main reason for rpi's success (over industrial SBCs) is the price.

I don't understand the second sentence quoted. Anyway. Driving DC current through a resistor results in a voltage drop. Driving AC current through a resistor results in ripple/noise. At those frequencies, a copper trace has high resistance (actually impedance) because of the inductive part. For...

You have to add the ripple/noise between SoC's GND and Cap's GND to the ripple between SoC's VCC and Cap's VCC to get the absolute voltage drop between Cap and SoC. All GNDs are connected, All VCCs are seperate. The idea is that the current/ripple from one VCC-GND pair (e.g. VCore) interferes...

I've managed to fry an µC with RF imission (30V/m (3x industrial limit)) once. That moment when you hold a measuring tape with λ/2 instead of cm or inch :D But stuff like that would depend on location (external RF source) and not really on load/core frequency. If GND "swings" at an offset to PE...

Nope, just working in electronics.

I'd say my guess is as good as anyone's. Luckily I never had to design stuff around such a huge and fast SoC, but the schematics' 10µF sound like high-ESR / low voltage; we do more low-level (non-linux) stuff with less than 120MHz. That being said, we still had our share of problems with "bad"...

It's not only about values, It's about the effective impedance, which also means "quality". Besides that, I haven't seen a post about what has been done, so this was just a suggestion. In the schematics I don't see any non-phy VCC that has no decoupling capacitor? Some VCC pins span across the...

Have you tried stacking other caps on top of the existing ones? With >=0603 and tweezers this could work for testing (without waiting for new pcbs).