In the reference manual of ADSP-BF548 EZ-KIT LITE , I have certain queries in the circuit of USB.
Please refer to Pg 120 of the attached manual.In this it has been mentioned that Pins 1&3 and pins 2&4 of jumper JP11 should always be populated. May I know what is the purpose of this jumper.
By using this jumper , we are supplying power to USB module of DSP , which can directly be given using 3.3V , then what is the need of generating 3.6V
The jumper is used to differentiate between device mode and OTG mode. When operating in OTG mode footnote 2 under the Absolute Maximum Ratings section in the datasheet (http://www.analog.com/static/imported-files/data_sheets/ADSP-BF542_BF544_BF547_BF548_BF54.pdf
) needs to be followed. The VBUS pin is 5V tolerant only if VDDUSB is applied. There is also further information on page 19-12 in the HRM (http://www.analog.com/static/imported-files/processor_manuals/ADSP-BF54x_hwr_rev1.2.pdf).