Talk:USB Host BoB Schematic

From wiki.gp2x.org

Is it possible to get better quality images of the schematics? The first is ok, but the others have hard-to-read text, especially any instances of '4' are garbled.

--slygamer 18:05, 10 February 2006 (PST)

Finally done. Took more time than I thought. (Did the first one a few days ago already ;-) Hope I didn't make any mistakes.

-- mcr42 20:52, 11 February 2006 (CET)

Thank you very much. That is much easier to decipher.

--slygamer 02:12, 13 February 2006 (PST)

I'm not sure about the resistor values in the USB filtering. The read 15k in Art103's picture, but the datasheet suggests 1.5k. Can somebody confirm the correct values ?

-- mcr42 16:30, 14 February 2006 (CET)

confirmed. The datasheet really suggests 15K on the host side. (http://www.ortodoxism.ro/datasheets/stmicroelectronics/7041.pdf, Pict. A1)

-- mcr42 10:30, 15 February 2006 (CET)

JTAG pinouts?

Were those fixed already? The page still says they're wrong and I can't seem to get any answers on the boards. Geminidomino 05:20, 29 May 2006 (PDT)

5V USB Power

The comment above the '3.3v to 5v schematic' is wrong. You can't make 5v out of 3.3 with a L7805. The 7805 accepts input from 20v to 6v, so you would need an external PSU. The best option is to use an LT1300 Step-Up converter. The advantage of this one is that it can be directly connected to the battery leads and thus provide up to 200mA (according to the data-sheet) of output power. The second edition of the GP2X already has a 5V supply inside. I'll report back as soon as I have these IC's --CopperCAT 02:00, 29 August 2006 (PDT)

Diode and capacitors specification

What kind of diode and capacitors are more appropriate for the 6-20V to 5V converter? What kind of capacitors are more appropriate for the USB Filtering? What I'm saying is: there are ceramic, electrolytic and tantalum capacitors. And Can the MC7805 do the same job of the L7805?


I am sorry if the questions sound stupid. I'm new at this

Personal tools