User`s guide

Power supply
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 two dierent ways: with USB power supply, and using
external adapters via adapter connector (CN16) or additional
screw terminals (CN15). External adapter voltage levels must be in
range of 9-32V DC and 7-23V AC. Use jumper J1 to specify which power
source you are using. Upon providing the power using either external adapter, or
USB power source, you can turn the board on using SWITCH 1 (Figure 3-1).
Figure 3-2: Power supply unit schematics
Figure 3-1: Power supply unit of EasyMx PRO
™
v7
VCC-5V
POWER
R59
2K2
LD1
C36
100nF
VCC-5V
2
1
3
GND
Vout
Vin
REG1
MC33269DT3.3
E14
10uF
3.3V VOLTAGE REGULATOR
VCC-3.3V
E16
220uF/35V/LESR
C35
100nF
1
2
3
4
8
7
6
5
SWC
SWE
CT
GND
DRVC
IPK
VIN
CMPR
U7
MC34063A
R66
0.22
R70
3K
VCC-SWC39
220pF
D6
MBRS140T3
L1 220uH
E18
220uF/35V/LESR
VCC-EXT
R71
1K
VCC-5V
J1
2 1 3
SWITCH1
VCC-USB
VCC-SW
+ -
D2
1N4007
D1
1N4007
D5
1N4007
D4
1N4007
CN16
CN15
E17
220uF/35V/LESR
5V SWITCHING POWER SUPPLY
power supply
page 6
EasyMx PRO
v7