Nokia 2650 Service Manual
RH-53/54
Nokia Customer Care
58
COMPANY CONFIDENTIAL
ISSUE 1 09/2004
Copyright © 2004 Nokia. All Rights Reserved.
RFMD FEM logic
Table 14: RFMD FEM logic
Analog Power control signals (TXC, VPC, VDET)
The pictures in the following page show the typical shapes of the control signals low band, right
side it for highest power – left side for lowest power. In all the pictures TXP is used a the trigger
point and is seen in the top of each picture. The difference between the high band and the low
band is that he high band signals looks the same with only small changes in level. The activat-
ing of high band Vdet starts 5us earlier than for low band.
side it for highest power – left side for lowest power. In all the pictures TXP is used a the trigger
point and is seen in the top of each picture. The difference between the high band and the low
band is that he high band signals looks the same with only small changes in level. The activat-
ing of high band Vdet starts 5us earlier than for low band.
Vtx
BS
VC1
VC2
Mode
VTX_B_P
VTX_B_P
Vant1
Vant2
Idle
0
0
0
0
Low Band RX
0
0
1
0
Low Band TX
1
0
1
0
High Band RX
0
1
1
0
High Band TX
1
1
1
0