Application Interface Specification; Power Supply; Power Supply Pin; Design Guide - SIM Tech SIMCom SIM5320J-TE Hardware Design

3

Application Interface Specification

3.1

Power Supply

The power supply range of SIM5320J-TE is from 3.3V to 4.2V. For the VBAT, the ripple due to
GSM/GPRS emission burst (every 4.615ms）may cause voltage drop, and the current consumption rises
typically to peak of more than 2A. So the power supply must be able to provide sufficient current up to
more than 2A. The following figure is the VBAT voltage ripple wave at the maximum power transmit
phase.
The test condition: VBAT =4.0V, VBAT maximum output current =2A, C
(ESR=0.7Ω) and C =1µF.
B
Figure 9: VBAT voltage drop during burst emission (GSM/GPRS)
3.1.1

Power Supply Pin

The VBAT pins are dedicated to connect the supply voltage.
Table 5: Pin description
Pin type Pin name
POWER VBAT
Note: When the module is power off, users must pay attention to the issue about current leakage. Refer to Chapter 3.10.2
Note2.
3.1.2

Design Guide

Mostly, user connects the VBAT pins with one power supply. Make sure that the input voltage at the
VBAT pin will never drop below 3.3V even during a transmit burst when the current consumption rises up
SIM5320J-TE_Hardware Design_V1.01
Min Typ
3.3 3.8
20
Smart Machine Smart Decision
=100 µF tantalum capacitor
A
Max Unit
4.2 V
2012-11-09