Smart Machine Smart Decision
4.
Application Interface
4.1.
Power Supply
The power supply range of SIM2000S is from 3.4V to 4.4V. Recommended voltage is 3.8V.
The power supply
must be able to provide sufficient current up to 600mA. For the VBAT input, a bypass capacitor (low ESR) such
as a 100 µF is strongly recommended.
A 5.1V/500mW Zener diode is strongly recommended, the diode can prevent chip from damaging by the
voltage surge. These capacitors and Zener diode should be placed as close as possible to SIM2000S VBAT
pins.
Figure 5: Reference circuit of the VBAT input
Table 4: Recommended Zener diode
Vendor
Part number
Power(watts)
Packages
1
On semi
MMSZ5231BT1G
500mW
SOD123
2
Prisemi
PZ3D4V2H
500mW
SOD323
3
Prisemi
PZ5D4V2H
500mW
SOD523
4
Vishay
MMSZ4689-V
500mW
SOD123
5
Crownpo
CDZ55C5V1SM
500mW
0805
The following figure is the reference design of +5V input power supply. The designed output for the power
supply is 4V, thus a linear regulator can be used.
Figure 6: Reference circuit of the LDO power supply
SIM2000S_Hardware_Design_V1.00
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2014-02-27