Ta2057N (Ic1) : Fm / Am If Amp & Detector - JVC UX-T77 Service Manual

TA2057N (IC1) : FM / AM IF AMP & Detector
1.Block d iagrams
AM
FM MIX
IF IN OUT Vstb
24 23
REG
FM
IF
AM
MIX
1 2
AM AM FM
RF IN S.SENS S.SENS
2.Pin function
Pin
No. I/O Symbol
1 I AM RF
2 AM S.SENS
3 FM S.SENS
4 - AM OSC
5 O AM OSC OUT
6 - VCC
7 I AGC
8 - GND
9 O IF OUT
10 O TU IND
11 O ST IND
12 O Rch OUT
AM
IF IN QUAD FM OUT AM OUT MPX IN
22 21 20
FM
DET
AM
IF
AM
BUFF
OSC
3 4 5
AM AM Vcc
OSC OSC
OUT
Function
AMRF signal input
AM local oscillation circuit
AM local oscillation signal output
Power supply
AGC voltage input terminal
Connect to GND
IF REQ signal output to IC2
Indicator drive output when tuning
Stereo indicator output
"H"mono . "L"stereo
Output Rch
LPF 1
19 18 17
AM
LEVEL
AM
SW
DET
IF
BUFF
IF REQ
AGC
SW
6 7 8
AGC GND IF OUT
/REQ
Pin
No. I/O Symbol
13 O Lch OUT
14 O VCO
15 O LPF2
16 O LPF1
17 I MPX IN
18 O AM OUT
19 O FM OUT
20 I FM QUAD
21 I AM IF IN
22 - Vst
23 O AM MIX OUT
24 I FM IF IN
LPF 2 VCO L OUT
16 15 14
VCO
DIVIDE
MUTE
DECODE
AM/FM
MONO
SW
TUN ST
LED LED
9 10 11
TUN ST R OUT
LED LED
Function
Output Lch
Voltage controlled terminal
When voltage of terminal is MONO
at "H" and ST at "L"
When voltage of terminal is AM at
"H" and FM at "L"
Multi plex signal input
AM detection signal output
FM detection signal output
Bypass to FMIF
Input of AMIF signal
Fixed voltage output terminal
Output terminal for AM mixer
Input of FMIF signal
UX-T77
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