NTE790 Integrated Circuit Dual Chroma Demodulator Description: The NTE790 has two sets of synchronous detectors with matrix circuits to achieve the R–Y, G–Y and B–Y color difference output signals. The chroma input signal is applied to Pin3 and Pin4 while the oscillator injection signal is applied to Pin6 and Pin7. The color difference signals, after matrix, have a fixed relationship of amplitude and phase nominally equal DC voltage levels. The outputs of the NTE790 are suitable for driving high level color difference or R, G, B output amplifiers. Emitter–follower output stages used to drive the high level color amplifiers have short–circuit protection. Absolute Maximum Rating: (TA = +25°C unless otherwise specified) DC Supply Voltage (Pin8 to Pin14) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27V Reference Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Vp–p Chroma Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Vp–p Total Device Dissipation (Up to TA = +70°C), PD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 530mW Derate Above TA = +70°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.7mW/°C Operating Ambient Temperature Range, Topr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40° to +85°C Storage Temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65° to +150°C Lead Temperature (During Soldering, 1/32” from seating plane, 10sec max), TL . . . . . . . . . +265°C Electrical Characteristics: (TA = +25°C and V+ = 24V unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit 16.5 – 26.5 mA – 9 – mA Static Characteristics Supply Current With Output Loads IT With No Output Loads G–Y, R–Y, B–Y Outputs S1 Closed S1 Open V9, V11, V13 S1 Closed 13.2 14.7 15.8 V Chroma Inputs V3, V4 S1 Open – 3.3 – V Reference Subcarrier V6, V7 S1 Open – 6.2 – V – – 0.8 Vp–p 8.0 – – Vp–p V11 5.5 – – Vp–p V9 1.2 – – Vp–p Demodulator Unbalance Maximum Color Difference Output Voltage V9, V11, V13 V3 = V4 = 0 V13 V3 = v4 = 0.6Vp–p Electrical Characteristics (Cont’d): (TA = +25°C and V+ = 24V unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Chroma Input Sensitivity V3 Adjust ec for 5V @ Pin13 (B–Y) – 0.2 0.35 Vp–p Relative R–Y Output V11 3.5 – 4.2 Relative G–Y Output V9 0.75 – 1.25 Vp–p – – 0.6 V VDC Difference Between any two Output Pins |V9|–|V13| ec = 0 Vp–p Input Impedance Reference Subcarrier ri6, 7 – 1.7 – kΩ Input Capacitance Reference Subcarrier ci6, 7 – 6 – pF Input Impedance at Chroma Inputs ri3, 4 – 0.95 – kΩ Input Capacitance at Chroma Inputs ci3, 4 – 6 – pF ro – 180 – Ω Output Resistance Pin Connection Diagram N.C. 1 14 GND N.C. 2 13 B – Y Output (–) Chroma 3 12 N.C. (+) Chroma 4 11 R – Y Output N.C. 5 10 N.C. R – Y Injection 6 9 G – Y Output B – Y Injection 7 8 VCC 14 8 1 7 .785 (19.95) Max .300 (7.62) .200 (5.08) Max .100 (2.45) .600 (15.24) .099 (2.5) Min