USB requires a crystal, but I doubt there's much, if any, power 
regulation or similar inside the USB chip.

The old USB chips did a huge amount of USB processing in software.  I 
imagine the newer revisions do most of it in hardware (they'd have to to 
get 12mbps) and since it's their first time with this peripheral they 
may be very liberal with die space.

But I bet it's simply because it's their first offered, and after 
several years they'll realize there is a use for an 8 pin USB pic.  4 
wires for USB port, two for crystal, and two more wires for anything - 
RS-485, blinky LEDs, serial LCD, dongles, small memory, etc.

I imagine there's a big market for 6 pin USB pics just for 
dongle/encryption usage alone.  They'd need to include a 16 bit 
multiplier and a 16 bit barrel shifter, perhaps a MAC.  And a lot of 
memory and code space.

-Adam

Charles Craft wrote:

>Anyone used the Maxim/Dallas Semi DS2480 or DS2490?
>
>Would a DS2490 and a Maxim/DS 1-wire temp sensor marry together so painlessly to overcome the expense?
>
>A PIC with USB connected to any of a zillion digital or analog temp sensors would be a lot less expensive.
>
>And to hijack the subject a little, why are the USB PICs so big? 
>Do they need a large die to support USB voltage or current reqs?
>The 18F flash USB chips are going to be 28 pin and larger parts.
>
>http://tinyurl.com/53uuw
>PIC18F2455/2550/4455/4550
>Data Sheet
>28/40/44-Pin High-Performance,
>Enhanced Flash USB Microcontrollers
>with nanoWatt Technology
>
>
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