UPC2533GS-01 NEC [NEC], UPC2533GS-01 Datasheet - Page 17

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

2.7 Station Detector Circuit Block
Since the PC2533 has two outputs (DC high/low signal (open collector) and AC IF signal (f = 450 kHz)), it can be
used according to DTS (digital tuning system) type. Input the SD request signal from DTS to pin 5.
set by external resistor between pin 7 and GND and by external resistor between pin 9 and GND.
by external resistor between pin 7 and GND (refer to Fig. 2-6).
The configration station detector (SD) circuit block is shown in Fig. 2-7.
The SD circuit stops scanning or seeking when a broadcast wave is received when auto scanning or seek tuning.
The SD sensitivity setting methods of the PC2533GS-01 and PC2533GS-02 differ.
With the PC2533GS-01, SD sensitivities in the IF counter output system and in the high/low output system are
With the PC2533GS-02, SD sensitivities in both the IF counter output system and high/low output system are set
From signal meter
circuit (Fig. 2-6)
Value of Resistor between Pin 9 or Pin 7 and GND
+
–
Detection comparator 2
1.0 V
Table 2-1 SD Sensitivity Setting Examples
SD output
(Active high)
Fig. 2-7 Station Detector Circuit Block
+
–
1.0 V
10
Detection comparator 1
51 k
24 k
10 k
5
From DTS (request)
–
+
To time constant
switchover circuit
(Fig. 2-6)
SD Sensitivity (AC, DC)
ON/OFF
27 dB V
29 dB V
33 dB V
SD AC output
6
8
450kHz IF input
(from T3)
PC2533
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