Smart Module Series
SC606T Series Hardware Design
SC606T_Series_Hardware_Design 39 / 116
The following figure shows the reference design for a +5 V power supply which is regulated with an LDO
(MIC29502WU) from Microchip. The typical output volage of the LDO is 3.8 V and the rated current of it is
5.0 A.
DC_IN
C1
C2
MIC29502WU
U1
IN
OUT
E
N
G
N
D
A
D
J
2
4
1
3
5
VBAT
100 nF
C3
470
μ
F
C4
100 nF
R2
100K
47K
R3
470
μ
F
470R
51K
R4
R1
1%
1%
Figure 5: Reference Design for Power Supply
If the module happens to get into an abnormal state, it is recommended to switch off and on its power
supply to restart it.
3.5. Turn-On and Turn-Off Timing
3.5.1. Turn On Module
The PWRKEY pin is pulled up to 1.8 V internally. Driving it low for at least 1.6 s turns on the module. It is
recommended to control the pin with an open drain/collector driver. A simple reference design is shown in
the following figure.
Turn on pulse
PWRKEY
4.7K
47K
>1.6 s
R1
R2
Q1
R3
1K
Figure 6: Turn On Module Using Driving Circuit
NOTE