PAMS Technical Documentation
System Module
NSB-5
Issue 1 03/01
Nokia Mobile Phones Ltd.
Page 67
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.
Table 22: First IF filter specifications
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.
Table 23: Second mixer specifications
Parameter
Minimum
Typical/
Nominal
Maximum
Unit/Notes
Operating temperature range
-30 ... +85
deg. C
Center frequency,
fo
487
MHz
Maximum Ins. loss at 1dB BW
3.0
4.5
dB
Group delay ripple at 1dB BW
1.0
us pp
Bandwidth relative to
fo
1dB bandwidth
10 dB bandwidth
13dB bandwidth
20 dB bandwidth
25 dB bandwidth
30 dB bandwidth
+/-200
+/-600
+/-800
+/-1000
+/-1600
+/-3000
kHz
kHz
kHz
kHz
kHz
kHz
Spurious rejection, fo +/->5MHz
35
dB
Terminating impedance (balanced)
input
output
240//-0.4
330//-0.2
ohms//pF
ohms//pF
Package size
length x width (max)
height (max)
3.8 x 3.8
1.8
mm
mm
Assembly
SMD Reflow
Parameter
Minimum
Typical/
Nominal
Maximum
Unit/Notes
Input frequency
487
MHz
Output IF frequency
87
MHz
Input LO frequency
400
MHz
Input LO level
200
600
mVpp
LO input resistance
200
ohms/at400MHz