Spartan-3A/3AN FPGA Starter Kit Board User Guide
www.xilinx.com
137
UG334 (v1.1) June 19, 2008
Measuring Power Across Voltage Supply Jumpers
R
Measuring Power Across Voltage Supply Jumpers
All regulator output supplies have an associated series jumper, as indicated in
Table 17-1
and shown in
Figure 17-1
. This allows for simple and easy current monitoring using just a
multimeter.
For example, to measure the Suspend mode current on the FPGA’s V
CCAUX
or V
CCINT
supplies, follow these steps.
Caution!
The Suspend feature must first be enabled in the actual FPGA application. All the
example designs initially shipped with the board have the Suspend feature enabled.
•
Disconnect power to the board.
•
Remove the series jumper associated with the supply to be measured, shown in
Table 17-2
. Locate jumper indicated in
Figure 17-1
.
•
Connect a digital multimeter across the jumper, as highlighted in
Figure 17-2
. If the
resulting current is negative, simply reverse the connections to the jumpers.
•
Set the meter to measure DC Amperes. Initially set the meter to the Ampere range. If
appropriate, switch to a lower range (for example, 200 mA) after initially measuring
current in the Ampere range.
Table 17-2:
FPGA Supply Rails and Associated Voltage Supply Jumper
FPGA Supply Rail
Associated Voltage
Supply Jumper
Default Voltage
V
CCINT
J9
1.2V
V
CCAUX
J11
3.3V
Figure 17-2:
Measuring Current (Power) Using a Multimeter
VCCINT (1.2V)
(Jumper J9)
VCCAUX (3.3V)
(Jumper J11)
(200 mA DC)
Set Current Range
(mA)
Measured Current
UG330_c17_02_032207
