Power Control Circuitry; Synthesizers; Technical Documentation Rf; Reference Oscillator - Nokia 9000i Service Manual

RAE/RAK–1N
RF

Power control circuitry

The power control loop consists of a power detector and a differential
control circuit. The power detector is a combination of a directional
coupler and a diode rectifier. The differential control circuit compares the
detected voltage and the control voltage (TXC) and controls voltage
controlled amplifier (in CRFRT) or the power amplifier. The control circuit
is a part of CRFRT.
Parameter
Supply voltage
using CRFRT
Supply current
using CRFRT
Power control range GSM
PCN
Power control inaccuracy
GSM
PCN
Dynamic range GSM
PCN
Input control voltage range
GSM
PCN

Synthesizers

Reference oscillator

In GSM and PCN the reference oscillator is a discrete VCXO and the
frequency is 26 MHz. In PCN the buffer amplifier for the reference
oscillator is located in the RF side near the local oscillator, although it is
drawn in the baseband schematic.
The oscillator signal is used for a reference frequency of the synthesizers
and the clock source for the baseband circuits.
Parameter
Center frequency
Frequency tolerance
Frequency control range
Supply voltage
Current consumption
Page 3– 22
Table 15. Power control specification
Minimum Typical /
Nominal
4.5 4.7
4.27 4.5
3.0
20
20
80
80
0.1
0.1
Table 16. VCXO specification
Minimum Typical /
Nominal
26
67
4.6 4.7
1.5
After Sales
Technical Documentation
Maximum Unit / Notes
4.9 V
4.73 V
5.0 mA
dB
dB
+/–1.0 dB
+/–1.0 dB
dB
dB
2.8 V
2.8
Maximum Unit / Notes
MHz
ppm, Vc=2.2 V
ppm
4.8 V
1.7 mA
Amendment 1 04/97