Sony NS3100 manual High speed video buffer amplifiers NS9100ES, Output Capacitor-Less OCL coupling

High speed video buffer amplifiers (NS9100ES)

If your television accepts an HDMI™ cable, you can enjoy a fabulous all- digital video connection. If not, you'll be happy to note that Sony® engineers are passionate about achieving exceptional performance from analog video connections. For example, the long analog cable runs found in many home theater installations can be highly capacitive. This tends to degrade the video signal, softening the picture and limiting the video bandwidth. To counter this possibility, the DVP-NS9100ES incorporates high-speed video buffer amplifiers. High slew-rate op amps handle large loads with very low overshoot. You get a powerful driving force for the video signals, even over long cable runs. As a result, the video signal delivered to the television has extremely low levels of noise, differential gain and differential phase.

MAIN Board
AV Decoder	IP Converter	VIDEO Encoder
STE5588CVB	CXD9866R	ADV7324
	16M SDRAM

Analog Video Board

Low pass filter For Progressive (Component)

Low pass filter

For Interlace (CVBS,S-Video)

Cr

Cb

Y

Y(S-Video)

C(S-Video)

CVBS

Buffer

Op-Amp

AD8058 X 6

Component

RCA OUT (525i/p)

S-Video

CVBS

Power Supply	+5V
For Analog Video Circuit
	-5V

Block diagram of the DVP-NS9100ES video circuit. You can see the separate digital circuit board (left) and analog circuit board (right). At center, you can see the nine channels of low-pass filtering. On the right are the video buffer op amps.

Output Capacitor-Less (OCL) coupling

In typical audio and video design, an output capacitor prevents the accidental passing of DC offset voltage from one component to the next. However, the mere presence of the output capacitor can affect the video frequency response and literally tinge the television picture with unwanted shading. And these effects can't be corrected by your television's picture controls. Sony's answer is a rigorous design that controls DC offset voltages from the start. You get reliable operation without performance-robbing output capacitors.

ES DVD Players 2005, Version 4.0 Page 26