MachXO3-9400 Development Board
Evaluation Board User Guide
© 2017 Lattice Semiconductor Corp. All Lattice trademarks, registered trademarks, patents, and disclaimers are as listed at
www.latticesemi.com/legal
. All other brand or product names are
trademarks or registered trademarks of their respective holders. The specifications and information herein are subject to change without notice.
FPGA-EB-02004-1.0
31
Figure 8.1. POT Circuit Design for VMON7
Rotate the POT clockwise to decrease the voltage as shown in
Figure 8.2
and to increase the voltage to VMON7, rotate
the POT counter-clockwise.
Decreasing
Wiper
Voltage
Wiper
CW
CCW
Clockwise
1
2
3
Figure 8.2. POT Wiper Description
8.3.
ASC Current Monitor
One of the ASC Current Monitors (IMONs) is connected to monitor the MachXO3 core current using resistor R181 as a
shunt. The IMON uses the differential voltage across R181 to monitor the current. The ASC has two IMONs: one is used
for lower voltage (-0.3 V to 5.9 V) current monitoring (pins 19 and 20) and the other HIMON (pins 17 and 18) is used for
higher voltage (4.5 V to 13.2 V) current monitoring. Pin 18 is a shared input pin used for both HIMON and HVMON
(which is VMON10.)
Table 8.3. ASC IMON Connections
Power Name
ASC Signal Name
ASC Pin Number
ASC Breakout Test Point
Comments
VCC_CORE
ASC_IMONP
19
TP30
R181 (0.020 Ω) is placed
between P/N node for
current measurement
ASC_IMONN
20
TP31
User Connected
ASC_HIMONP
17
TP28
HV IMON positive input
ASC_HVMON
18
TP29
Dual Function: HV IMON
negative input and
VMON10 input
The VCC_CORE current measurement is designed according to
Figure 8.3
.
POT1
3314G-1-103E
1
3
2
POT1_WIPER
R277
1k
ASC_VMON7
+3.3V_ASC
