Nokia 2650 - Baseband - RF Interface; Internal Signals and Connections; Audio

RH-53/54
Nokia Customer Care 8-System Module
18 COMPANY CONFIDENTIAL Issue 2 06/2005
Copyright © 2005 Nokia. All Rights Reserved.
Baseband - RF interface
The interface between the baseband and the RF can be divided into three categories:
- The digital interface from the UPP to the RF ASIC (Mjoelner). The serial digital interface is
used to control the operation of the different blocks in the RF ASICs.
- The analogue interface between UEM and the RF. The analogue interface consists of RX and
TX converter signals. The power amplifier control signal TXC and the AFC signal comes as well
from the UEM.
- Reference clock interface between Mjoelner and UPP, which supplies the 26Mhz system
clock for the UPP.
■ Internal Signals and Connections
The tables below describe internal signals. The signal names can be found on the schematic
for the PWB.
Audio
Table 7: Internal microphone
Table 8: Internal speaker (Differential output EARP & EARN)
Signal Min
No
m
Max
Conditi
on
Note
MIC1P (Differential input P) - 5mV - TBD
MIC1N (Differential input N) - 5mV - TBD
MICB1 (Microphone Bias) 2.0
V
2.1
V
2.25 V DC
External loading of MICB1 - - 600uA DC
Signal Min
No
m
Max Units Note
Output voltage swing 4.0 - - Vpp Differential output
Load Resistance (EARP to
EARN)
25,5 27,
2
28,9 W 2*10Ù 5% +
7,2Ù±10%
Load Capacitance (EARP to
EARN)
- - 50 nF