Nokia 6255 Service Manual
Nokia Customer Care
Baseband Description and Troubleshooting
6255/6255i6256/6256i (RM-19)
Issue 2 05/2005
©2005 Nokia Corporation Company Confidential
Page 13
Table 3 includes the UEME RF regulators.
The charge pump that is used by VR1A is constructed around the UEME. The charge
pump works with the 1.2MHz clock (CBUS) oscillator and gives a 4.75V regulated output
voltage to the RF.
pump works with the 1.2MHz clock (CBUS) oscillator and gives a 4.75V regulated output
voltage to the RF.
Table 3: RF Regulators
Regulator
Maximum
Current (mA)
Vout (V) Notes
VR1A
10
4.75
Enabled when cell receiver is on
VR1B
10
4.75
Enabled when the transmitter is on
VR2
100
2.78
Enabled when the transmitter is on
VR3
20
2.78
Enabled when SleepX is high
VR4
50
2.78
Enabled when the receiver is on
VR5
50
2.78
Enabled when the receiver is on
VR6
50
2.78
Enabled when the transmitter is on
VR7
45
2.78
Enabled when the receiver is on