GS1881 Gennum Corporation, GS1881 Datasheet
GS1881
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GS1881 Summary of contents
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... H rate. This windowing the GS1881 and GS4881, gates the back porch pulse in the GS4881 and GS4981, and generates the horizontal sync output in the GS4981 ...
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... Note 2: Measured from slicing point of input falling edge to 50% point of composite sync falling edge. ORDERING INFORMATION Part Number Package Type GS1881 - CDA 8 PDIP GS1881 - CKA 8 SOIC GS1881 - CTA 8 TAPE GS1881 - IDA 8 PDIP GS1881 - IKA 8 SOIC GS1881 - ITA 8 TAPE GS1881 - CKAE3 8 SOIC GS1881 - CTAE3 8 TAPE GS1881 - IKAE3 8 SOIC 520 - 680 SET ...
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GS4881 ELECTRICAL CHARACTERISTICS PARAMETER Supply Voltage Supply Current Video Input (Pin 2) (a) Signal Level (b) Clamp Current (c) Delay to raising of Nosync flag Video input held high (d) Sync Tip Clamp Voltage Sync Slice Level R Pin Reference ...
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GS4981 ELECTRICAL CHARACTERISTICS PARAMETER Supply Voltage Supply Current Video Input (Pin 2) (a) Signal Level (b) Clamp Current (c) Delay to raising of Nosync flag Video input held high (d) Sync Tip Clamp Voltage Sync Slice Level R Pin Reference ...
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TYPICAL PERFORMANCE CHARACTERISTICS 700 600 500 400 300 200 100 SCAN RATE (kHz) Fig Scan Rate SET 700 600 500 400 300 200 100 0 0 100 200 300 400 R (k ...
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TEMPERATURE CHARACTERISTICS Commercial Temperature Range ( ° -25 - TEMPERATURE (°C) Fig. 7 Composite Sync Delay Variation vs Temperature -10 ...
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... Video are supply and input Input Back Porch Output GS4881 GS4981 The GS1881 does not gate the Back Porch which allows for total pin compatibility with the LM1881. VERTICAL SYNC OUTPUT (pin 3) The vertical sync interval is detected by integrating the 1 / horizontal lines. 2 composite sync pulses ...
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... HORIZONTAL OUTPUT (pin 7 GS4981) As mentioned above, the odd/even field output GS1881 and GS4881 is generated by comparing vertical sync with an internal horizontal sync signal. This horizontal sync signal is a true horizontal signal (i.e. maintained during the vertical interval) and is outputted on pin 7 for the GS4981. A delay of 190 ns from the video input and a width of 6.5 µ ...
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... VOLTAGE REGULATOR R_SET (Pin 6) TIMING CURRENTS C SYNC HORIZONTAL WINDOWING CIRCUIT NOSYNC VERTICAL DETECTOR 1.2V BACK PORCH DETECTOR Fig. 17 GS1881 Block Diagram C SYNC HORIZONTAL WINDOWING CIRCUIT NOSYNC B PEN VERTICAL DETECTOR 1.2V BACK PORCH DETECTOR Fig. 18 GS4881 Block Diagram COMPOSITE SYNC OUTPUT (Pin 1) ...
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... BACK PORCH OUTPUT GS4881, GS4981 BACK PORCH OUTPUT GS1881 HORIZONTAL OUTPUT GS4981 VERTICAL SYNC OUTPUT GS1881, GS4881, GS4981 ODD/EVEN OUTPUT GS1881, GS4881 Fig. 20 GS1881, GS4881, GS4981 Video Sync Separator Timing Diagram 520 - SYNC WINDOWING CIRCUIT NOSYNC B PEN VERTICAL DETECTOR 1.2V BACK PORCH DETECTOR Fig ...
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APPLICATION NOTES (1) Choosing the Appropriate Input Coupling Capacitor to Optimize Slicing Level and Hum Rejection The video designer can adjust the slicing level by choosing the value of the input coupling capacitor. The relationship between slicing level and input ...
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The interfering hum component is defined by cos(2 ƒ HUM P where Peak voltage of AC hum P ƒ = Frequency of hum ( Hz) HUM The maximum rate of change ...
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Photograph 3 shows the amount of sync clipping for a 560 source resistor. A graph of V versus R CLIP Figure 23, and Figure 24 shows the corresponding capacitor value for a particular series resistor to provide a corner frequency ...
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... REVISION NOTES Added lead-free and green information. Gennum Corporation assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement. 520 - the start of an odd field the vertical output ends in the middle of the horizontal line and a high will be latched ...