Data Sheet

©2007-2008 CADEKA Microcircuits LLC

www.cadeka.com

7

Figure 3. Typical Output Configuration

Power Supply Decoupling

For optimum performance, power supply decoupling is re-

quired. Figure 4 shows the recommended usage of power

supply decoupling capacitors. The 0.1µF decoupling ca-

pacitor must be placed as close to pin 4 as possible, <

0.1” or < 2.5mm, to be effective. The larger, 1µF capaci-

tor can be placed further away.

Figure 4. Recommended Power Supply Decoupling

Power Dissipation

TBD

0

0.5

1

1.5

2

2.5

-40

-20

0

20

40

60

80

Ambient Temperature (°C)

SOIC-8

Figure 5. Maximum Power Derating

Power Dissipation Considerations with DC-Coupled Loads

When driving DC loads, the supply current is much higher

than in AC applications and care must be taken to dis-

sipate the extra heat generated. The output signal will

swing from about 0.3V to 2.3V for full swing video. In

the worst case condition, an all white screen with dual DC

loads, the additional thermal rise over the quiescent con-

dition is about 20°C. An easy way to help distribute this

extra heat is to place a ground plane under the part and

add ground plane on the bottom of the board immediately

under the part with vias between the two planes.

The CLC3800 is designed primarily for low voltage opera-

tion with supply values between 3.0V and 5.5V, but larger

supplies can be used. In this situation, DC loads may not

be possible due to thermal considerations. With single DC

loads on all three channels and a 12V supply, the thermal

rise is an additional 45° this gives a total temperature rise

of about 57°.

220µF

220µF

CLC3800

IN1

OUT1

IN2

IN3

OUT3

+Vs

OUT2

GND

75Ω

75Ω

75Ω

75Ω

220µF

75Ω

75Ω

Video Cables

AC-Coupling Caps

are Optional

8

7

6

5

1

2

3

4

75Ω

CLC3800

IN1

OUT1

IN2

IN3

OUT3

+Vs

OUT2

GND

+3V or +5V

0.1µF

1.0µF

8

7

6

5

1

2

3

4