Document
FM-Sound IF with SCART Switch and Volume Control
TBA 121-5
Bipolar IC
Features
q q q q
Outstanding limiting qualities Few external components Integrated de-emphasis resistor Low harmonic distortion factor
P-DIP-16
Type TBA 121-5
Ordering Code Q67000-A5137
Package P-DIP-16
Functional Description FM-IF amplifier, consisting in a limiter amplifier with FM demodulator. The AF section contains a SCART-record/playback switch as well as AF output with volume control. The control of the volume is controlled via an analog control input, and the SCART switch is controlled via a switch input. Application Application of the IC is intended in mono TV sets. Circuit Description In its FM section, the component contains an eight stage, symmetrical limiter amplifier with subsequent coincidence demodulator. The AF section contains an analog switch for the SCARTrecording / playback function as well as an analog volume control with AF output.
Semiconductor Group
91
06.94
TBA 121-5
Pin Functions Pin No. 1 2 3 4 5 6 Function Ground Limiter amplifier operating point feedback (RF decoupling of IF amplifier with appropriate capacitors is required!) Limiter amplifier operating point feedback and low end (RF decoupling of IF amplifier with appropriate capacitors is required!) IF-amplifier output (emitter follower) IF-amplifier output (emitter follower) Demodulator input with high impedance input and internal 15 kΩ supply resistor (if an LC circuit is used, the Q is determined by the damping resistance across pins 6 and 7) Demodulator input with high impedance input and internal 15 kΩ supply resistor (if an LC circuit is used, the Q is determined by the damping resistance across pins 6 and 7) Connection for de-emphasis capacitor (a series resistor of 11 kΩ is integrated) AF output of the SCART interface (emitter follower with short circuit limiter) AF input 1 of the SCART interface (IF branch) Rec/Pb switch input AF input 2 of the SCART interface (SCART input) Volume control IF output (emitter follower) + VS supply voltage IF input (limiter amplifier input; internal resistor between pin 16 and 3 typ. 800 Ω)
7
8 9 10 11 12 13 14 15 16
Semiconductor Group
92
TBA 121-5
Expanded Block Diagram, Part 1
Semiconductor Group
93
TBA 121-5
Expanded Block Diagram, Part 2
Semiconductor Group
94
TBA 121-5
Block Diagram
Semiconductor Group
95
TBA 121-5
Absolute Maximum Ratings TA = 0 to 70 ˚C Parameter Supply voltage IF-input voltage DC voltage DC voltage DC voltage DC voltage DC voltage DC voltage DC voltage DC voltage DC voltage DC voltage DC current DC current DC current DC current Junction temperature Storage temperature Thermal resistance (system-air) Operating Range Supply voltage Frequency range Ambient temperature in operation Symbol min. Limit Values max. 16 600 V mVrms V V V V V V V V V V mA mA mA mA ˚C ˚C K/W 0 0 0 0 0 0 0 0 0 0 0 0 0 0 –1 –1 – 55 Unit
VS VI 16 rms V2 V3 V6 V7 V8 V9 V11 V12 V13 V16 I4 I5 I9 I14 Tj Tstg Rth SA
VREF VREF VS VS VS-2 VREF VS VS VS VREF
2 2 2 2 150 125 80
VS f TA
10.5 0.1 0
15.75 12 70
V MHz ˚C
Semiconductor Group
96
TBA 121-5
Characteristics TA = 0 to 70 ˚C; VS = 10.5 to 15.5 V; refer to test circuit Parameter Current consumption Input voltage for limiting response (VQ 9, 14 = – 3 dB) SCART-output voltage Symbol min. Limit Values typ. 29 60 max. 37 100 mA µV 21 Unit Test Condition
IS VI 16 rms
f I 16 = 5.5 MHz; ∆ f = 30 kHz; f mod = 1 kHz V I 16 = 10 mV; ∆ f = 30 kHz; f mod = 1kHz f I 16 = 5.5 MHz V13 = 4.8 V; ∆ f = 30 kHz; f mod = 1 kHz; f I 16 = 5.5 MHz V I 16 = 10 mV; ∆f=0
THD = THD min
∆ f = 30 kHz; V I 16 = 10 mV; f mod = 1 kHz f I 16 = 5.5 MHz V13 = 4.8 V
VQ 9
500
650
mV
AF-output voltage
VQ 14
450
650
mV
DC component
VQ 9 VQ 14 THD 9 THD 14
4.8 6 1 1.1
V V % %
Total distortion factor
AM suppression (test conditions for reference point)
a AM9, 14
50
60
dB
V I 16 = 500 µV; m = 30%; f mod = 1 kHz; f I 16 = 5.5 MHz; ∆ f = 30 kHz; V I 16 = 10 mV V13 = 5-0 V
Volume control range Maximum SCARTinput voltage Gain between SCART input (pin 10) and AF output (pin 14) Switching Voltage, Muting ON (AF OFF) OFF
V14 VI 12 GSC
80 2 0
dB Vrms dB
V11 ≥ 8 V ≤ 12 V V13 = 4.8 V
V3 V3
8 0
VS
3
V V
Semiconductor Group
97
TBA 121-5
Characteristics (cont’d) TA = 0 to 70 ˚C; VS = 10.5 to 15.5 V; refer to test circuit Parameter Design Notes Input resistance Output resistance Output resistance Input resistance Input impedance Residual IF voltage Hum suppression VS/VQ 9, 14 (without de-emphasis C) Crosstalk attenuation (test conditions for reference point) Symbol min. Limit Values typ. max. kΩ 100 200 20 800 10 30 Ω Ω kΩ Ω mV dB ∆ V S = 500 mVrms f S = 100 Hz Unit Test Condition
R I 6, 7 RQ9 R Q 14 R I 10, 12 Z I 16 VQ 9, 14 (IF) a qh
10
a 12-14
60
dB
V 12 = 2 Vrms; RF mode: ∆ f = 30 kHz; f mod = 1 kHz; f I 16 = 5.5 MHz V I 16 = 10 mV f I 16 = 5.5 MHz; V13 = 4.8 V; V I 16 = 300 mV; f mod = 1 kHz; ∆ f = 30 kHz;
IF MUTE = ON; measured selectively at 1 .