UPC2533GS-01 NEC [NEC], UPC2533GS-01 Datasheet - Page 13

• Manufacturer Part Number: UPC2533GS-01
• Description: AM TUNER FOR ELECTRONIC TUNING CAR RADIOS
• Manufacturer: NEC [NEC]

2.3 MIX2 Block
by the AGC.
match the 450 kHz ceramic filter.
MIX2 blocks.
a result, IFT design is not restricted by the need to match ceramic filter impedance. For turn ratio, etc., only conversion
gain need be taken input account, so it is easy to design.
Note Output impedance and input impedance of Buff2 are 2 k
MIX2 (Q201 to Q208) is a DBM with a configuration similar to that of MIX1.
The major difference from the MIX1 is that MIX2 is equipped with a current control circuit for output and is controlled
Input impedance of MIX2 is 330
IF signal input from pin 23 is also input to the detector of the RF AGC. The RF AGC is detected by both MIX1 and
The Buff1 and Buff2 ensure impedance matching between MIX1 and MIX2 outputs and each ceramic filter. As
From 10.7 MHz BPF
To RF AGC circuit (Fig. 2-4)
28
Bias
circuit
R211
R210
R209
23
R207
Q201
V
17
Q205
CC
to match the 10.7 MHz ceramic filter. Output impedance of Buff2 is 2 k
Q202
Current control
circuit
24
Q206
Fig. 2-3 MIX2 Block
Note
Q203
25
Q207
Q204
R208
Q208
R212
14
and 30 k , respectively.
+
13
OSC2
From IF AGC (Fig. 2-6)
Xtal
12
Q203
11
22
Buff2
To IF amplifier
Note
PC2533
21
13
to