Nokia 6020b Service Manual
Issue 1 03/2005
COMPANY CONFIDENTIAL
17
Copyright © 2005 Nokia. All Rights Reserved.
RM-31
7 - System Module
7 - System Module
Nokia Customer Care
External SRAM and Flash
The Combo-Memory is a multi chip package memory which combines 128 Mbit (8Mx16) muxed
burst multibank flash and 16 Mbit muxed CMOS PSRAM (Pseudo SRAM: DRAM with SRAM
interface).
burst multibank flash and 16 Mbit muxed CMOS PSRAM (Pseudo SRAM: DRAM with SRAM
interface).
The combo is supplied by single 1,8 V for read, write and erase operations. For accelerated
flash programming, Vpp = 9.0 V has to be applied to VPP input of the combo device.
flash programming, Vpp = 9.0 V has to be applied to VPP input of the combo device.
The combo memory is housed in a 44-ball FBGA.
■
Energy management
The energy management of RM-31 is based on BB 4.0 architecture. A so-called semi fixed bat-
tery (BL-5B) supplies power primarily to UEMEK ASIC and the RF PA. The UEMEK includes
several regulators to supply RF and Baseband. It provides energy management including pow-
er up/down procedure.
tery (BL-5B) supplies power primarily to UEMEK ASIC and the RF PA. The UEMEK includes
several regulators to supply RF and Baseband. It provides energy management including pow-
er up/down procedure.
Modes of operation
The baseband engine has six different functional modes: Since the UEMEK controls the regu-
lated power distribution; each of these states affects the general functionality of the phone.
lated power distribution; each of these states affects the general functionality of the phone.
1. No supply
2. Backup
3. Acting Dead
4. Active
5. Sleep
6. Charging
No Supply
In NO_SUPPLY mode, the phone has no supply voltage. This mode is due to the disconnection
of the main battery and backup battery or low battery voltage level in both of the batteries.
of the main battery and backup battery or low battery voltage level in both of the batteries.
The phone is exiting from NO_SUPPLY mode when sufficient battery voltage level is detected.
The battery voltage can rise either by connecting a new battery with VBAT > V
The battery voltage can rise either by connecting a new battery with VBAT > V
MSTR+
or by con-
necting charger and charging the battery above V
MSTR+
.
Backup
In BACKUP mode the backup battery has sufficient charge but the main battery can be discon-
nected or empty (VBAT < V
nected or empty (VBAT < V
MSTR
and VBACK > VBU
COFF
).
The VTRC regulator is disabled in BACKUP mode. VRTC output is supplied without regulation
from the backup battery (VBACK). All the other regulators are disabled.
from the backup battery (VBACK). All the other regulators are disabled.
Acting Dead
If the phone is off when the charger is connected, the phone is powered on but enters a state
called ”Acting Dead”. To the user, the phone acts as if it was switched off. A battery-charging
alert is given and/or a battery charging indication on the display is shown to acknowledge the
user that the battery is being charged.
called ”Acting Dead”. To the user, the phone acts as if it was switched off. A battery-charging
alert is given and/or a battery charging indication on the display is shown to acknowledge the
user that the battery is being charged.