ADV473

–12–

REV. A

Analog Signal Interconnect

The ADV473 should be located as close as possible to the out-

put connectors to minimize noise pickup and reflections due to

impedance mismatch.

The video output signals should overlay the ground plane, and

not the analog power plane, to maximize the high frequency

power supply rejection.

For maximum performance, the analog outputs should each

have a 75

Ω load resistor connected to GND. The connection

between the current output and GND should be as close as pos-

sible to the ADV473 to minimize reflections.

For more information on circuit board design and layout, see

application note entitled “Design and Layout of a Video Graph-

ics System for Reduced EMI” available from Analog Devices,

Publication No. E1309-15-10/89.

COMPONENT

DESCRIPTION

VENDOR PART NUMBER

C1 – C5

0.1

µF CERAMIC CAPACITOR

ERIE RPE112Z5U104M50V

C6

10

µF TANTALUM CAPACITOR

MALLORY CSR13G106KM

L1

FERRITE BEAD

FAIR-RITE 2743001111

R1, R2, R3

75

Ω 1% METAL FILM RESISTOR

R

SET

1% METAL FILM RESISTOR

0.1

µF

ANALOG POWER PLANE

IOR

IOG

IOB

V

AA

ADV473

V

REFIN

75

Ω

75

Ω

V

REFOUT

CO-AXIAL CABLE

(75

Ω)

GND

BNC

CONNECTORS

75

Ω

75

Ω

75

Ω

MONITOR

(CRT)

0.1

µF

10

µF

POWER SUPPLY DECOUPLING

(0.1

µF CAPACITOR FOR

EACH V

0.1

µF

L1

(FERRITE

BEAD)

COMP

COMP

+5V (V

0.1

µF

+5V (V

+5V (V

R

SET

140

Ω

R

SET

0.1

µF

75

Ω

Figure 8. Typical Connection Diagram (Internal Voltage

Reference)

Package Thermal Considerations

In certain circumstances, the 135 MHz version of the ADV473

may require forced air cooling or the addition of a heatsink. The

68-pin PLCC has a heat resistance characteristic as shown in

Table VIII.

It should be noted that information on Package Thermal Characteris-

tics published herein may not be the most up to date at the time of

reading this. Advances in packaging technology will inevitably lead

to improvements in thermal data. Please contact your local sales office

for the most up-to-date information.

Table VIII. Thermal Resistance vs. Airflow

Air Velocity

(Linear Feet/Min)

0 (Still Air)

50

100

200

θ

°C/W)

32

26

19

16

OUTLINE DIMENSIONS

Dimensions shown in inches and (mm).

Plastic Leaded Chip Carrier

(P-68A)

0.954 (24.23)

0.950 (24.13)

SQ

0.995 (25.27)

0.885 (22.48)

SQ

61

10

44

9

43

26

60

TOP VIEW

PIN 1

IDENTIFIER

27

0.029 (0.74)

0.027 (0.69)

0.019 (0.48)

0.017 (0.43)

0.175 (4.45)

0.169 (4.29)

0.925 (23.50)

0.895 (22.73)

0.104 (2.64) TYP

0.050

(1.27)

TYP