UPC2533GS-01 NEC [NEC], UPC2533GS-01 Datasheet - Page 12

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

2.2 MIX1 Block
(Q101 to 108) multiplies the local oscillation signal by RF signal, and converts to the resonance frequency of IFT T1
for output.
be directly input to CMOS LSI for use by the PLL synthesizer.
12
From
LPF
Note Output impedance and input impedance of Buff1 are 330
MIX1 (Q101 to Q108) is a DBM (double balanced mixer).
MIX1 output is supplied to 10.7 MHz ceramic filter via Buff1 (output impedance: 330 ) for impedance matching.
The local oscillation signal is applied to the bases of Q101 to Q104, and the RF signal to the base of Q105. MIX1
The local oscillation signal is output from pin 1 via Q109 (OSC Buff). It has an amplitude of 110 dB V and can
The RF signal applied to the base of Q105 is also input to the detector of the RF AGC circuit.
V
T
28
33
30
1
Q109
R11
2
OSC1
3
+
Q105
R107
Q101
Fig. 2-2 MIX1 Block
31
Q102
Q106 Q107
T1
Q103
32
Q108
Q104
R108
and 15 k , respectively.
R109
R110
To RF AGC circuit (Fig. 2-4)
17
V
CC
29
R111
Buff1
R112
To 10.7 MHz
BPF
Note
27
PC2533