–5–

REV. A

AD9701

DIE LAYOUT AND MECHANICAL INFORMATION

Die Dimensions . . . . . . . . . . . . . . . . 107

104

15 (

±2) mils

Pad Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

4 mils

Metalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aluminum

Backing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . None

Passivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oxynitride

Die Attach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gold Eutectic

Bond Wire . . . . . . . 1.25 mil Aluminum; Ultrasonic Bonding or

1 mil Gold; Gold Ball Bonding

APPLICATIONS INFORMATION

Raster scan video displays image data on a line by line basis,

with timing and control signals inserted between the lines. The

control signals include the horizontal synchronization pulses,

which are used to align the display circuitry at the beginning of

each line. After the complete video image is displayed on the

monitor, the process begins again with the next image. The ver-

tical reset pulse(s) that initiate this timing sequence are located

between each video image.

Raster Graphics Configuration for TTL Systems

The image data is distinguished from the timing information by

its location relative to the blanking level. The blanking reference

level is at the blackest extreme of the image data and all timing

signals are designed to fall below the blanking level so as not to

be seen on the monitor. The actual image data is located above

the blanking level and it may be further separated from the tim-

ing signal by the setup level. The setup level is simply a buffer

zone between the timing and image data.

Generation of the timing signals for the AD9701 is controlled

by the

COMPOSITE BLANKING and the COMPOSITE

SYNC inputs. In normal operation, the output level of the

AD9701 is forced to the blanking level (black) with the

COM-

POSITE BLANKING control so that when the synchronization

occurs, it will not interfere (be seen) with the monitor image.

The

COMPOSITE SYNC control forces the output level below

the blanking level, generating the synchronization pulse.

The “grey scale” is the image intensity range located above the

blanking level by the amount of the setup level. The setup level

is “reference black,” the darkest displayable picture intensity.

The top of the “grey scale” is “reference white” or the brightest

picture intensity. As an 8-bit device, the AD9701 divides the

“gray scale” into 256 individual levels.

Normal raster scan waveforms divide the region between the

blanking level and reference white into 100 IRE units (Interna-

tional Radio Engineers). The setup level can range from 0 to 20

IRE units but typically is around 10 IRE units, and the synchro-

nization pulse level typically falls 40 IRE units below the blank-

ing level. For the AD9701, the reference white level is 10 IRE

In terms of priority, the

REFERENCE WHITE control over-

rides the data inputs, but both

COMPOSITE SYNC and

COMPOSITE BLANKING override the data inputs and the

REFERENCE WHITE control. A fourth control is active at all

times,

10% BRIGHT, which adds approximately 10 IRE units

to the output level no matter what the input state of the

AD9701. The

10% BRIGHT control is primarily used to high-

light areas of the video image.

As with any high-speed device, the AD9701 requires a substan-

tial low impedance ground plane and high quality ground con-

nections to achieve the best performance. Performance can also

be improved with adequate power supply decoupling near the

supply pins of the AD9701. In ECL mode, the output of the

AD9701 is designed to drive 75

Ω cable directly, with 75 Ω ter-

minations to ground at both ends of the cable. For TTL con-

figurations, the output should be terminated to +5.0 V through

an 82

Ω resistor (see circuit below).

Standard Reconstruction Configuration