Document
TOSHIBA BIPOLAR LINEAR INTEGRATED CIRCUIT SILICON MONOLITHIC
TA8876FA
FOR LCD TVS, PIF, QIF, AND SIF SYSTEMS
TA8876FA
FEATURES
PIF circuit
· High-speed response peak AGC with dual time constant
· Forward / Reverse RF AGC output
· Output with black noise inverter
· Output without black noise inverter
· Video output adjustment
· Single polarity AFT output
· Built-in sync. separation circuit
QIF circuit
· Intercarrier demodulation block with same structure as in PIF circuit
Weight: 0.63g (Typ.)
· Independent mean value AGC detection
SIF circuit
· Sound IF amplification and detection
· Quadrature-type detection circuit
· Use of a ceramic discriminator device makes the SIF circuit adjustment-free.
· Sound mute switch
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BLOCK DIAGRAM
TA8876FA
TERMINAL FUNCTION TERMINAL LIST
PIN No.
PIN NAME
1 1st-AGC 2 2nd-AGC 3 RF-AGC Output 4 VIDEO ADJ. 5 AGC Delay 6 PIF VCC 7 PIF Input 1 8 PIF Input 2 9 PIF GND 10 QIF Input 1 11 QIF Input 2 12 QIF AGC 13 FM Detection Input 14 Limiter Output 15 Sound Output 16 QIF Output 17 Limiter Input (RF-AGC Switch) 18 QIF / SIF GND
FUNCTION
1st AGC filter terminal 2nd AGC filter terminal RF AGC output (Reverse / Forward switchable) Video output adjustment terminal (Connect capacitor, normally) RF AGC delay point adjustment terminal PIF circuit power supply terminal PIF signal input terminal PIF signal input terminal PIF circuit GND terminal QIF signal input terminal QIF signal input terminal QIF AGC filter terminal Sound FM detector input terminal Sound limiter output terminal Sound output terminal QIF signal output terminal Sound limiter input terminal (Also used for RF-AGC switching) QIF and SIF circuit GND terminal
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TA8876FA
PIN No.
PIN NAME
19 QIF Coil 1
20 QIF Coil 2
21 QIF / SIF VCC 22 Sync. Separation Output
23 AFT Coil 1
24 Video Coil 1
25 Video Coil 2
26 AFT Coil 2
27 Sync. Separation Input
28
Video Output 1 (Output without noise inverter)
29
Video Output 2 (Output with noise inverter)
30 AFT Output
FUNCTION
QIF detector carrier extraction terminal QIF detector carrier extraction terminal QIF and SIF circuit power supply terminal Sync. signal output terminal AFT detector coil terminal PIF detector carrier extraction terminal PIF detector carrier extraction terminal AFT detector coil terminal Sync. signal input terminal Video detection output terminal (Output without noise inverter) Video detection output terminal (Output with noise inverter) AFT control voltage output terminal
TERMINAL FUNCTION
PIN No.
PIN NAME
FUNCTION
INTERFACE CIRCUIT
1 PIF AGC
2
Uses dual time constant to speed up AGC.
To mute picture, connect pin 1 to GND.
RF AGC 3
Output
Emitter follower-type RF AGC output. Max. output 3 mA (typ.)
3 2001-05-10
PIN No.
PIN NAME
FUNCTION
Video signal output voltage adjustment
terminal. Changing this terminal
Video Output
voltage, it is possible to adjust video
4 Adjustment
signal output voltage to 1.0 Vp-p.
To prevent noise, connecting capacitor
(0.01 µF) to GND is recommended.
TA8876FA
INTERFACE CIRCUIT
RF AGC 5
Delay
Changing comparator reference voltage adjusts RF AGC delay point.
6 PIF VCC
Insert bypass condenser between this terminal and pin 9.
7 PIF Input
8
PIF signal input terminal. Input impedance is 5 kΩ (typ.).
9 PIF GND
Insert bypass condenser between this terminal and pin 6.
— —
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PIN No.
PIN NAME
FUNCTION
10 QIF Input
11
QIF signal input terminal. Input impedance is 5 kΩ (typ.).
TA8876FA
INTERFACE CIRCUIT
12 QIF AGC
AGC terminal of QIF detector circuit.
13 FM Detection Input
Sound detection terminal for coil, which is connected between this terminal and pin 14.
15 Sound Output FM detector circuit output terminal.
Sound detection terminal for coil, which is connected between this terminal and pin 13.
14 Limiter Output Applying ceramic discriminator sets this circuit to non-adjustable circuit.
To mute sound, connect pin 13 to GND.
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PIN No.
PIN NAME
FUNCTION
16 QIF Output
QIF detection output terminal. Connect this terminal to SIF input via BPF.
For BPF matching, see function of pin 17.
SIF Input 17
RF AGC SW 18 QIF GND
SIF
Connect to pin 16, via BPF.
This terminal also functions as output polarity switching circuit of RF AGC output.
Internal impedance is designed to be 2 kΩ. Externally connecting 2 kΩ between this terminal and GND outputs reverse AGC and changes input impedance to 1 kΩ.
Externally connecting a 2 kΩ-resistor between this terminal and VCC outputs forward AGC and changes input impedance to 1 kΩ.
Insert bypass condenser between this terminal and pin 21.
19 QIF Coil
20
This terminal connects QIF detection coil.
21 QIF VCC SIF
Insert bypass condenser between this terminal and pin 18.
22 Sync . 27 Separation
Sync. separation circuit required for tuner’s search function.
TA8876FA
INTERFACE CIRCUIT
— —
6 2001-05-10
PIN No.
PIN NAME
FUNCTION
24 Video Coil
25
Connects video detection coil.
TA8876FA
INTERFA.