User Manual

LARA-R2 series - System Integration Manual
UBX-16010573 - R02 Objective Specification System description
Page 18 of 148
1.5 Supply interfaces
1.5.1 Module supply input (VCC)
The modules must be supplied via the three VCC pins that represent the module power supply input.
The VCC pins are internally connected to the RF power amplifier and to the integrated Power Management Unit:
all supply voltages needed by the module are generated from the VCC supply by integrated voltage regulators,
including V_BCKP Real Time Clock supply, V_INT digital interfaces supply and VSIM SIM card supply.
During operation, the current drawn by the LARA-R2 series modules through the VCC pins can vary by several
orders of magnitude. This ranges from the pulse of current consumption during GSM transmitting bursts at
maximum power level in connected-mode (as described in section 1.5.1.2) to the low current consumption
during low power idle-mode with power saving enabled (as described in section 1.5.1.4).
LARA-R211 modules provide separate supply inputs over the three VCC pins:
 VCC pins #52 and #53 represent the supply input for the internal RF power amplifier, demanding most of
the total current drawn of the module when RF transmission is enabled during a voice/data call
 VCC pin #51 represents the supply input for the internal baseband Power Management Unit and the internal
transceiver, demanding minor part of the total current drawn of the module when RF transmission is
enabled during a voice/data call
Figure 3 provides a simplified block diagram of LARA-R2 series modules internal VCC supply routing.
53
VCC
52
VCC
51
VCC
LARA-R204
Power
Management
Unit
Memory
Baseband
Processor
Transceiver
RF PMU
LTE PA
53
VCC
52
VCC
51
VCC
LARA-R211
Power
Management
Unit
Memory
Baseband
Processor
Transceiver
RF PMU
LTE / 2G PAs
Figure 3: LARA-R2 series modules internal VCC supply routing simplified block diagram