First If Filter; Second Mixer (Vhf) In Crfu_2A - Nokia NSB-5 Series Technical Documentation Manual

PAMS Technical Documentation

First IF Filter

The first IF filter is a SAW filter to improve the blocking conditions caused by inband spu-
rious signals which cause a noise rice effect in second mixer if looser filter is used.
Parameter
Operating temperature range
Center frequency, fo
Maximum Ins. loss at 1dB BW
Group delay ripple at 1dB BW
Bandwidth relative to fo
1dB bandwidth
10 dB bandwidth
13dB bandwidth
20 dB bandwidth
25 dB bandwidth
30 dB bandwidth
Spurious rejection, fo +/->5MHz
Terminating impedance (balanced)
input
output
Package size
length x width (max)
height (max)
Assembly

Second Mixer (VHF) in CRFU_2a

Second mixer is double balanced common emitter Gilbert cell. The mixer is optimized for
differential drive; however, it can also be used with single ended drive. The LO-port is AC
coupled internally.
Parameter
Input frequency
Output IF frequency
Input LO frequency
Input LO level
LO input resistance
Issue 1 03/01
Table 22: First IF filter specifications
Typical/
Minimum
Nominal
-30 ... +85
487
3.0
+/-200
35
240//-0.4
330//-0.2
3.8 x 3.8
1.8
SMD Reflow
Table 23: Second mixer specifications
Typical/
Minimum
Nominal
487
87
400
200
200
Nokia Mobile Phones Ltd.
System Module
Maximum Unit/Notes
deg. C
MHz
4.5 dB
1.0 us pp
+/-600 kHz
+/-800 kHz
+/-1000 kHz
+/-1600 kHz
+/-3000 kHz
kHz
dB
ohms//pF
ohms//pF
mm
mm
Maximum Unit/Notes
MHz
MHz
MHz
600 mVpp
ohms/at400MHz
NSB-5
Page 67