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FIBOCOM L610-LA Series Hardware Guide
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Recommended
Capacitor
Application
Description
Battery power can be properly
reduced to 100~220uF capacitor
1uF,100nF
Digital signal noise
Filter clock and digital signal
interference
33pF
700, 850/900 MHz band
Filter low band RF interference
8.2pF
1700/1800/1900,2100/2300,2500/2600MHz
band
Filter middle/high band RF
interference
The power stability ensures the normal operation of L610 modules. The design requires special attention
to the power ripple below 300mV (the circuit ESR < 150mohm). When the module is operating in GSM
mode (Burst transmit), the maximum operating current can reach 2A, and the power voltage needs to be
at least 3.3V. Otherwise, the module may power off or restart. The power limit is shown in Figure 3-3:
Figure 3- 3 Power Limit
Note:
Clients are recommended to add a TVS (recommended model: SMBJ15A) to the VBAT input, so
as to improve the anti-surge capability of the product.
3.2.2 1.8V Output
L610 modules output 1.8V voltage through the VDD_EXT for use of the internal digital circuits of the
modules. The voltage is the logic level voltage of the module and can be used to indicate that the module
is on or off, or for external low current ( < 80mA) circuit. If it is not in use, keep it in floating status. The
logic level of VDD_EXT is defined as follows:
Parameter
Minimum
Typical
Maximum
Unit
VDD_EXT
1.71
1.8
1.89
V
3.2.3 Power Consumption
The power consumption of L610 module in the case of 3.8V power supply is shown in the following table:
