EL2090C

EL2090C EL2090C 100 MHz DC-Restored Video Amplifier Features  Complete video level restoration system  0 01% differential gain and 0 02 differential phase accuracy at NTSC  100 MHz bandwidth  0 1 dB flatness to 20 MHz  Sample-and-hold has 15 nA typical leakage and 1 5 pC charge injection  System can acquire DC correction level in 10 ms or 5 scan lines of 2 ms each to IRE  VS e g 5V to g 15V  TTL CMOS hold signal General Description The EL2090C is the first complete DC-restored monolithic video amplifier sub-system It contains a very high-quality video amplifier and a nulling sample-and-hold amplifier specifically designed to stabilize video performance When the HOLD logic input is set to a logic 0 during a horizontal sync the sampleand-hold amplifier may be used as a general-purpose op-amp to null the DC offset of the video amplifier When the HOLD input goes to a logic 1 the sample-and-hold stores the correction voltage on the hold capacitor to maintain DC correction during the subsequent scan line The video amplifier is optimized for video characteristics and performance at NTSC is nearly perfect It is a current-feedback amplifier so that b 3 dB bandwidth changes little at various closed-loop gains The amplifier easily drives video signal levels into 75X loads With 100 MHz bandwidth the EL2090 is also useful in HDTV applications The sample-and-hold is optimized for fast sync pulse response The application circuit shown will restore the video DC level in five scan l...