SA1787 Datasheet, PDF (7/19 Pages) Silan Microelectronics Joint-stock – SINGLE-CHIP TUNER IC FOR CAR RADIOS

SA1787
PIN DESCRIPTION
Pin No.
1
Pin Name
ANT D
2
RF AGC
3
F.E.GND
4
OSC
AM/FM OSC
5
BUFF
VCC
6
AM/FM SW
7
AM OSC
Noise AGC
8
Sen
9
AGC ADJ
10
AM 2nd OSC
11
Memory
12
Memory
13
Pilot IN
14
GND
15
MPX OUT (L)
16 MPX OUT (R)
17
Pilot OUT
18
Pilot OUT
19
Sep ADJ
20
VCO
I/O
Descriptions
O
An antenna damping current for FM pin diode drive output
RF AGC voltage to control the LNA second gate. AGC is applied at the
O
voltage of Vcc-Vbe.
I/O Ground of AM/FM front end
I/O Oscillator connection for FM 1st Mixer
O
AM/FM oscillator buffer output
V6=8VÆFM and pin6 is FM front end VCC
I/O
V6=openÆAM
AM first oscillator for up conversion
I/O
This circuit can oscillator up to the SW band.
Noise sensitivity setting pin for setting up the medium field(about 50
I
dBµ)
I
The AGC Dynamic Range adjustment pin for 20 to 30dBµ
O
Oscillator circuit for AM 2nd Mixer
I/O
Memory circuit for noise canceller operation.
I/O
I
The PLL circuit MPX signal input pin.
I/O Ground for the N.C., MPX, and MRC circuits.
O
MPX output
O
O
Output pin for the pilot canceller signal.
The resistor and capacitor between pin17 and pin18 need to be
O
adjusted with the sample-to-sample variations.
The input level of subdecoder is varied through the resistor and
I
capacitor outside.
(The output level of MONO and MAIN remain unchanged)
I/O Attach a 912KHz crystal oscillator outside.
21 PHASE COMP. I/O Pilot phase detector
22 PHASE COMP. I/O Pilot phase detector
In seek mode, pin23 is FM/AM IF counter buffer.
Also, pin23 functions as switch:
IF Counter
23
SK/ST SW
In FM mode:
Pin23 = 5V: Seek mode
I/O Pin23 = 2.5V: Forced SD mode
Pin23 = 0 V: Reception mode
In AM mode:
Pin23 = 5 V: Seek mode
Pin23 = 0 V: Reception mode
HANGZHOU SILAN MICROELECTRONICS CO.,LTD
Http://www.silan.com.cn
REV:1.0
2008.08.29
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