TA7678 LINEAR INTEGRATED CIRCUIT VIDEO AND SOUND IF AMPLIFIER FOR MONOCHROME TV RECEIVERS DESCRIPTION The Contek TA7678 is a monolithic integrated circuit designed for the VIF and SIF stage in B/W television receivers. The UTC TA7678 is used for forward AGC Type. FEATURE VIF STAGE *High gain wide brand IF amplifier 50dB at 45MHz *Gain reduction with excellent stability: 55dB at 45MHz DIP-16 *Excellent DG/DP and S/N characteristics SIF STAGE *Excellent limiter characteristics *Excellent AM Rejection *Large undistorted audio output voltage with quadrature detector BLOCK DIAGRAM Contek Contek Microelectronics Co.,Ltd. CONTEK http://www.contek-ic.com E-mail:[email protected] 1 TA7678 LINEAR INTEGRATED CIRCUIT ABSOLUTE MAXIMUM RATINGS (Ta=25 PARAMETER C) SYMBOL VALUE Supply Voltage Vcc 15 UNIT V Open Loop Voltage V4 15 V V Video DC output current (note) V12 6 Operating Temperature Topr -20 to +65 C Storage Temperature Tstg -55 to 155 C Power dissipation PD 1.4 W ELECTRICAL CHARACTERISTICS(Ta=25 PARAMETER TEST CIRCUIT Recommended Supply Voltage C,Vcc=12V,fp=45.75MHz,unless otherwise specified) SYMBOL TEST CONDITIONS Vcc Quiescent circuit current 1 Iccq Video DC output 1 V12 Terminal 5 voltage 1 V5 MIN. TYP. MAX. UNIT 10.8 12 13.2 V 35 50 65 mA S1:OFF,S3:2,S5:2,S4:1 5.2 5.5 5.8 V S1:ON,S3:2,S5:2,S4:1 3.5 4.4 5.3 V 4.6 6.0 7.2 V S1:ON,S3:2,S5:2,S4:1 Terminal 7 voltage 1 V5 S1:ON,S3:2,S5:2,S4:1 RF AGC Residual Output Voltage 1 V4(sat) S1:OFF,S3:2,S5:2,S4:1 0.5 V RF AGC Leak Current 1 I4(leak) S1:OFF,S3:1,S5:2,S4:1 1 mA Video sensitivity 2 SVI Note 1 60 150 250 mVrms AGC Range 2 VAGC(IF) Note 2 60 64 Sync Tip Level Voltage (pin12) 2 Vsync Note 3 2.3 2.5 dB 2.7 V (pin12) Maximum IF Input Voltage 2 VI(MAX) Note 4 100 120 White Noise Threshold (pin12) 2 VWTH Note 5 5.8 6.2 6.6 mVrms V Note 5 3.7 4.1 4.5 V Note 5 1.4 1.6 1.8 V 3.7 V (pin12) White Noise Clamp Level (pin12) 2 VWCL (pin12) Black Noise Threshold (pin12) 2 VBTH (pin12) Black Noise Clamp Level (pin12) 2 VBCL(pin12) Note 5 2.9 3.3 Video Frequency Response 3 Gv(IF) Note 6 4.5 5.5 Suppression of carrier 4 CL Note 7 40 50 dB 4 I2nd Note 8 40 50 dB 920kHz Beat level 4 I920 Note 9 33 38 Differentital Gain 5 DG Note 10 Differential Phase 5 DP Note 10 VIF Input Impedance 6 RIN Note 11 1.5 Maximum Avaliable Current 1 I4(MAX) Note 12 7 Suppression of 2 nd Carrier 7 CIN MHz dB 10 dB 3.5 5 C 3.0 6.0 k 3.0 10.0 pF mA RF AGC delay Point Range 2 Vin(delay) Note 13 5.0 7.0 9.0 V Video output level 2 Vo0 Note 14 2.25 2.5 2.75 V Contek Microelectronics Co.,Ltd. CONTEK http://www.contek-ic.com E-mail:[email protected] 2 TA7678 SIF STAGE LINEAR INTEGRATED CIRCUIT (Ta=25 C,Vcc=12V,fo=45.75MHz,unless otherwise specified) PARAMETER TEST CIRCUIT SYMBOL TEST CONDITIONS MIN. TYP. MAX. UNIT SIF Output Voltage 3 VSO Note 15 200 400 Input limiting voltage 8 Vi(lim) Note 16 200 400 mVrms AM Rejection Ratio 8 AMR Note 17 40 45 dB Recovered Output Voltage 8 VOD Note 18 0.5 0.75 Total Harmonic distortion 8 THD Note 18 Maximun Audi Output Voltage 8 VOM Noet 19 SIF Input Impedance 7 RIN(SIF) 1.0 10 9 RO(AF) Note 20 10 mVrms Vrms 2.0 4.0 CIN(SIF) Audio Output Impedance 600 % Vp-p 20 30 kW 3 10 pF 15 20 kW Note: 1. VAGC=11.5V,VIF Input : 45.5MHz,1kHz,30 AM Modulation. Adjust VIF input Vi level so that the detected output of 2. VAGC=4V. Measure VIF input level vi is same as note 1 DA=20log(Vi /Vi)(dB) 3. VIF input : f=45.75MHz CW 15mVrms. Measure the DC level of Pin12. 4. VIF Input : f=45.75MHz APL 100%.87.5% AM Modulation. Pin 14 Open Pin 12 with high impedance probe will be 0.8Vp-p and measure the input Level. 4.1. Adjust VIF inpt level 50mVp-p and measure the detected output level Vo(p-p) 4.2. Then increase the input level so that the detected output level will be 1.1* Vo(p-p) and measure the input level. 5. 6. VAGC=8V. VIF input : f=45.75MHz+-10MHz variable or sweep 15mVrms measure DC level of Pin12. VAGC=8V. SG1:45.75MHz CW. SG2:45.65~27MHz variable. 6.1. Setting output of SG1 s o that the DC level of Pin12 will be 6.2. Setting output of SG1(45.65MHz so that the AC level of Pin12 will be 0.5Vp-p. 6.3. Decreasing frequency of SG2 until the AC level of Pin 12 will be 0.35vp-p(-3dB of 0.5Vp-p) then read FSG2=F, fBW=45.75-F MHZ 7. SG1:45.75MHz, 1kHz 80% AM Modulation 100mVrms. SG2 ,SG3:OFF. Setting VAGC so that the output AC 8. Measure 2 level of Pin12 will be 2.7Vp-p. Measure CL of Pin12 after setting to 0% AM of SG1. nd of Pin12 same as note 9. Contek Microelectronics Co.,Ltd. CONTEK http://www.contek-ic.com E-mail:[email protected] 3 TA7678 9. LINEAR INTEGRATED CIRCUIT VAGC=8V. SG1 :45.75MHz(P:picture) 100mVrms, SG2:41.25MHz(S: Sound) 32mVrms(-10dB of SG1),SG3:42.17MHz(C:Chroma) 32mVrms(-10dB of SG1) 9.1. Setting VAGC so that the output Pin12 will be 3.0V DC. 9.2. Measure the level difference between the C-level and 920kHz. 10. VAGC=8V. VIF Input : f=45.75MHz video signal (RAMP) 87.5% AM 100mVp-p. Setting ATT so that the SYNC TIP 11. VAGC=5V. f=45.75MHz. Measure RIN and CIN. level of Pin12 will be 2.5VDC measure DP and DG. 12. S1=ON, S3=2,S5=1,S4=2 13. Pin 14 open. VIF Input : 45.75MHz CW 20mVrms. 13.1. Adjust the voltate of Pin 3 so that the voltage of Pin4 will be 6.0V DC. 13.2. Measure the Pin 3. 14. Pin 14 open. VIF Input: 45 .75MHz 100% APL 87.5% AM Modulation signal amplitude 50mVp-p mesure the detected output voltage (white peak to SYNC TIP) 15. PIN14: Op en. SG1 :45.75MHz CW 100mvrms. SG2 :41.25MHz CW 25mVrms. Measre SIF(4.5MHz) output voltage at Pin12. 16. SIF input: f=4.5MHz FM fMOD=400Hzm Df=+-25kHz 16.1. Adjust SIF input level 100mVp-p and measure the detected output level Vos. 16.2. Then decrease the i nput level so that the detected output level will be 3dB down of Vos and measure the input level. 17. SIF input: f=4.5MHz, FM fMOD=400Hz 18. SIF input: f=4.5MHz, fM fMOD=400Hz 19. SIF input: f=4.4~4.6MHz variable or sweep measure the outjput DC voltage change. 20. Df=+-25kHz. AM 30%,input level Vins=80dB m. Df=+-25kHz. Input level Vins=80dB m SIF inptut : f=4.5MHz, FM FMOD=400Hz Df=+-25kHz, input level Vins=80dB m. 20.1. Measure the detected output voltagae vOA with Rx= . 20.2. Then, adjust Rx so that the d etected output voltage will be VOA/2 and measure Rx. 1. DC TEST CIRCUIT Contek Microelectronics Co.,Ltd. CONTEK http://www.contek-ic.com E-mail:[email protected] 4 TA7678 LINEAR INTEGRATED CIRCUIT 2. AC TESTS CIRCUIT 3. VIDEO FREQUENCY RESPONSE & SIF OUTPUT VOLTAGE TEST CIRCUIT 4. INTER MODULATION TEST CIRCUIT Contek Microelectronics Co.,Ltd. CONTEK http://www.contek-ic.com E-mail:[email protected] 5 TA7678 LINEAR INTEGRATED CIRCUIT 5. DG,DP TEST CIRCUIT 5. INPUT IMPEDANCE TEST CIRCUIT Contek Microelectronics Co.,Ltd. CONTEK http://www.contek-ic.com E-mail:[email protected] 6 TA7678 LINEAR INTEGRATED CIRCUIT 7. SIF INPUT IMPEDANCE TEST CIRCUIT 8. VIN(LIM) AMR, VOD,THD VOM TEST CIRCUIT 9. AUDIO OUTPUT IMPEDANCE TEST CIRCUIT UTC UNISONIC TECHNOLOGIES CO., LTD. 7 TA7678 LINEAR INTEGRATED CIRCUIT TYPICAL APPLICATION CIRCUIT Contek Microelectronics Co.,Ltd. CONTEK http://www.contek-ic.com E-mail:[email protected] 8