E a s y M x
P R O
v 7 a
U s e r M a n u a l
P A G E 7
POWER
SUPPLY
PO
WER SUPPL
Y
Board contains switching power supply that creates stable voltage and current
levels necessary for powering each part of the board. Power supply section contains
specialized MC33269DT3.3 power regulator which creates VCC-3.3V power supply,
thus making the board capable of supporting 3.3V microcontrollers. Power supply
unit can be powered in three different ways: with USB power supply (CN20), using
external adapters via adapter connector (CN30) or additional screw terminals
(CN31). External adapter voltage levels must be in range of 9-32V DC and 7-23V AC.
Use jumper J9 to specify which power source you are using. Upon providing the power
using either external adapters or USB power source you can turn on power supply by
using SWITCH 1 (Figure 3-1). Power LED ON (Green) will indicate the presence of
power supply.
J9C
D3
1N4007
D4
1N4007
D5
1N4007
D6
1N4007
CN30
CN31
VCC-5V
POWER
R68
2K2
LD78A
E18
220uF/35V/LESR
E19
220uF/35V/LESR
1
2
3
4
8
7
6
5
SWC
SWE
CT
GND
DRVC
IPK
VIN
CMPR
U8
MC34063A
R69
0.22
R74
3K
VCC-SW
C39
220pF
D7
MBRS140T3
L1 220uH
VCC-EXT
R76
1K
VCC-5V
2
1
3
SWITCH1
VCC-USB
VCC-SW
+
-
5V SWITCHING POWER SUPPLY
C38
100nF
VCC-5V
2
1
3
GND
Vout
Vin
REG1
MC33269DT3.3
E16
10uF
VCC-3.3V
E17
220uF/35V/LESR
C37
100nF
3.3V VOLTAGE REGULATOR