Motorola A920 Service Manual page 82

A920: Voltage Regulators
PCAP
B+
V2
VA_2_775V
V5
VGPS_RF_2_775V
V9
VRF_REF_2_475V
VBOOST_5_5V
VBOOST_LX
VBUCK_2_25V
VBUCK_LX
V_VIB V_VIB
VSIMC
Vsim2
VMMC
Vaux3
VAUX4_3V
Vaux4
VHOLD_EXT_EN
VBUCK2_1_6V
LX2
VHOLD_OUT
Description
Voltage regulation is provided by the PCAP IC (U3000). Multiple regulators are used to provide better isolation between sensitive load circuitry and noisy circuitry.
The regulators and their load circuitry are described below:
· VBOOST_LX(VBOOST_5_5V) - VUSB abd V10 input voltage regulator
· VBUCK_LX(VBUCK_2_25V) - V1, V3, V4, V7, and V8 input voltage regulator
· LX2(VBUCK2_1_6V) - Helen core
· V_VIB - Vibrator
· Vsim2(VSIMC) - SIM card interface
· Vaux1(VRF_TX_2_775V) - RF TX circuits
· Vaux2(VRF_RX_2_775V) - RF RX circuits
· Vaux3(VMMC_2_8V) - SD/MMC interface
· Vaux4(VAUX4_3V) - Image processor, USB xcvrs (Application processor and Bluetooth USB)
· VUSB - PCAP USB xcvr
· V1(VMEM_1_875V) - Application Processor Flash I/O, Application Procesor DRAM I/O, Baseband Processor Flash Core
· V2(VA_2_775V) - Audio
· V3(VLVIO_1_95V) - Magic LV I/O, WCSP
· V4(VRF_REF_1_875V) - RF reference
· V5(VGPS_RF_2_775V) - GPS RF
· V6(VHVIO_2_775V) - HV I/O, Display(20), Imager(12), GPS Baseband(8), GPS Flash, Application Processor SDRAM core(200)
· V7(VRF_DIG_1_875V) - RF digital
· V8(VBLUETH_1_875V) - Bluetooth
· V9(VRF_REF_2_475V) - RF Reference
· V10(VRF_HV_5V) - RF HV
CAM_SHUTDOWN
HELEN
B+
PCAP
VUSB
V10
V3
V4
V7
V8
V1
Q3980
U3980
PCAP
VCAM_3V
U3910
V6_ Drv
VUSB_3_3V
VRF_HV_5V
Vaux1_ Drv
VLVIO_1_95V
VRF_REF_1_875V
VRF_DIG_1_875V
Vaux2_ Drv
VBLUETH_1_875V
VMEM_1_875V
B+
Switcher
VOMAP_1_6V
Q3220
B+
Q3403
V6
VHVIO_2_775V
B+
Q3502
VRF_TX_2_775V
Vaux1
VRF_REF_2_775V
B+
Q3610
VRF_RX_2_775V
Vaux2
U3220
VMAIN_1_55V
Supply