There is a single regulator chip, that provides 1.8 and 3.3V outputs. The 1.2V was already made with a switching regulator. 2.5? Audio? Most people say that using a switching regulator for audio purposes is not a good idea. Anyway, there are 2 visible inductors on my new 'pi, so I'd guess that the 2.5V is still a linear regulator. But with the current draw very low on that voltage line, the current savings would not warrant the cost increase.
(The original 'pi was designed to be possible-to-produce / sell for $35, at say around 20k pieces. Now we know that they sell in the millions, so it has become possible to select slightly more expensive components that when purchased in the higher numbers end up still being cheaper than the original estimate at 20k items).
Re: Analog in:
Most microcontrollers/CPUs, like the for example attiny44, atmega328, PIC16F84, STM32F030 and STM32F405 all have an on chip ADC module. The BCM2835, simply doesn't have an ADC on the chip! So either you mount a separate ADC chip on each and every 'pi (i.e. expensive: 99% of the users are not going to be using it!), or you tell those that need the ADC to get one to connect on their expansion board. They decided against this last option. And I agree.
And that's what this raspberry pi is all about. It is more or less a breakout for broadcom 2835 processor, with many on-chip-features brought out to connectors on the board. You can buy many "development kits" for other CPUs that have an LCD, and a bunch of other on-board-chips so you can test/develop for that CPU. But those boards tend to cost in the $100-$300 (and up) range. So the "raspberry pi" is a very good "other strategy" for what you get for that kind of money. But alas: No ADC.
The new Raspberry Pi B+ is awesome, but it would have been better if they had increased its RAM and Processing speed, Does any one know why didn't they do that ???
Does the release of rpi b+ mean we should be seeing the release of the official rpi dsi display attachment?? If I remember correctly , something similar happened before the release of the cam module.
Yes we do: it does not "out - of - the - box." The hardware to do POE properly costs about 20% of the cost of a 'pi. Maybe only 5-10% at bigger volumes. So the backwards-compatbile and "easy enough fro most people" solution was chosen: Power using a micro-USB connector.
You can add a POE module yourself. Either a compliant one and feed the 'pi with a 5V made from the POE output. Or a "hacked" version where e.g. you put a voltage (e.g. 12-24V) on the unused wires in the cable and just use a DCDC converter to make 5V near the 'pi. (take care not to feed that voltage back into the switch and check what you need to do at the side of the 'pi. (maybe feeding it to the 'pi is acceptable, maybe not))
I've designed a special I/O & Audio carrier card for the RPi Model B - are these not available anymore? Is the new B+ mechanically identical (with new stand-off holes)?
