User guide

WA_DEV_FEX20_UGD_002 Rev 004 March 08, 2011 46
Fastrack Xtend User Guide
Interfaces
Refer to the following table for the list of recommended speaker characteristics.
Table 21. Recommended Speaker Characteristics
Feature
Values
Type
10mW, electro-magnetic
Impedance
Z = 30 to 50
Sensitivity
110dB SPL min. (0dB = 20µPa)
Frequency response
Compatible with GSM specifications
5.1.3. USB Interface
Aside from the serial interface, the mini-USB interface (USB Slave) may also be used to directly
communicate with the Fastrack Xtend.
This USB slave feature is also used for USB charging feature if the optional battery accessory is
available. When plugged-in through the mini-USB interface, it will start the charging circuit.
When using with the optional battery accessory, ensure that the current limit of the USB slave is
greater than 100mA.
Figure 21. Mini-USB Connector
Refer to the following table for the pin description of the mini-USB connector.
Table 22. Mini-USB Pin Description
Pin #
Signal
Description
1
VBUS
+5V Power supply
2
D-
Differential data interface positive
3
D+
Differential data interface negative
4
ID
Not connected
5
GND
Ground
The USB slave interface complies with USB 2.0 protocol signaling and electrical interface.
The USB interface features:
 12Mbit/s full speed transfer rate
 3.3V type compatible
 USB Soft-connect feature