
Reproduction forbidden without Fibocom Wireless Inc. written authorization - All Rights Reserved
FIBOCOM L610 Series Hardware Guide
Page 28 of 59
Figure 3-2 Recommended power design
Note:
VBAT_RF and VBAT_BB are included in the subsequent documents.
Power filter capacitor design is shown in the following table:
Recommended
Capacitor
Application
Description
220uF x 2,10uF
Regulating capacitor
Reduce power fluctuations during
module operation, requiring low ESR
capacitor
LDO or DCDC power requires not
less than 440uF capacitor
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, 2500/2600
MHz 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 <
150mΩ). When the module is operating in GSM mode
(Burst transmit), the maximum operating current can reach 2 A, and the power voltage needs to be at
least 3.4 V. Otherwise, the module may power off or restart. The power limit is shown in Figure 3-3: