Nokia 5140 Manuales De Servicio
NPL-4/5
System Module and User Interface
Nokia Customer Care
Page 76
Copyright © 2004 Nokia Corporation. All rights reserved.
Issue 1 05/04
DC characteristics
Regulators
The transceiver baseband section has a multi function analog ASIC, UEMEK, which con-
tains among other functions six pieces of 2.78 V linear regulators and a 4.8 V switching
regulator. All the regulators can be controlled individually by the 2.78 V logic directly or
through a control register. Normally, direct control is needed because of switching speed
requirement: the regulators are used to enable the RF-functions which means that the
controls must be fast enough.
tains among other functions six pieces of 2.78 V linear regulators and a 4.8 V switching
regulator. All the regulators can be controlled individually by the 2.78 V logic directly or
through a control register. Normally, direct control is needed because of switching speed
requirement: the regulators are used to enable the RF-functions which means that the
controls must be fast enough.
The seven regulators are named VR1 to VR7. VrefRF01 is used as the reference voltages
for the Helgo, VrefRF01 (1.35V) for the bias reference and for the RX ADC (analog-to-
digital converter) reference.
for the Helgo, VrefRF01 (1.35V) for the bias reference and for the RX ADC (analog-to-
digital converter) reference.
The regulators (except for VR7) are connected to the Helgo. Different modes of operation
can be selected inside the Helgo according to the control information coming through
the RFBus.
can be selected inside the Helgo according to the control information coming through
the RFBus.
List of the needed supply voltages
Volt. source
Load
VR1
PLL charge pump (4.8 V)
VR2
TX modulators, ALCs, driver
VR3
VCTCXO, synthesizer digital parts
VR4
Helgo pre-amps, mixers, DtoS
VR5
dividers, LO-buffers, prescaler
VR6
LNAs, Helgo baseband (Vdd_bb)
VR7
VCO
VrefRF01
ref. voltage for Helgo
Vbatt
PA