Hardware Manual XE166 Low End Easy Kit Board V1.5
General Information about XE166 Easy Kit Board
Hardware Manual
12
V1.5, 2011-03
2.6
Easy Kit Power Supply concept
The Easy Kit USB Power Supply concept allows the user to work with the Kit without an external Power Supply.
If the USB power supply is not sufficient, an additional regulated DC power supply can be used.
Figure 5
Easy Kit Power Supply concept
By means of the Power Supply Jumper JP201, USB, or the external power Supply can be selected to run the Easy
Kit. The Setup for the Jumper JP201 is shown in
below.
The USB specification provides a 5 V supply on a single wire from which connected USB devices may draw power.
The specification provides for no more than 5.25 V and no less than 4.35 V between the +ve and -ve bus power
lines.
Initially, a device is only allowed to draw 100 mA. It may request more current from the upstream device in units
of 100 mA up to a maximum of 500 mA. In practice, most ports will deliver the full 500 mA or more before shutting
down power, even if the device hasn't requested it or even identified itself. If a (compliant) device requires more
power than is available, then it cannot operate until the user changes the network (either by rearranging USB
connections or by adding external power) to supply the required power.
Table 3
Power Supply Jumper configuration
Name in
schematic
Configuration
Description
JP201
Power Supply via USB Interface
(Default)
JP201
Power Supply via Power Plug
Power Supply
USB Supply
Powe
r
LEDs
JP201
1
DC
6 … 12V
5V
5V
XE166
CPU
1
2
3
2
3
1
