LTC6903/LTC6904

5

69034fa

PI FU CTIO S

GND (Pin 1): Negative Power Supply (Ground). Should be

tied directly to a ground plane for best performance.

SDI ( Pin 2 ): Serial Data Input. Data for serial transfer is

presented on this pin.

SCK (Pin 3): Serial Port Clock. Input, positive edge trig-

gered. Clocks serial data in on rising edge.

SEN (Pin 4): Serial Port Enable (6903 Only). Input, active

LOW. Initiates serial transaction when brought LOW,

finalizes transaction when brought HIGH after 16 clocks.

serial port address.

CLK (Pin 5): Auxiliary Clock Output. Frequency set by

serial port.

CLK (Pin 6): Main Clock Output. Frequency set by serial

port.

OE (Pin 7): Asynchronous Output Enable. CLK and CLK are

set LOW when this pin is LOW.

kept free from noise and ripple. It should be bypassed

directly to a ground plane with a quality 0.1

µF capacitor.

Additional bypass may be necessary for operation at high

frequency or under larger loads.

TYPICAL PERFOR A CE CHARACTERISTICS

Output Waveform at 68MHz

Output Waveform at 20MHz

Output Spectrum at 20MHz

3468 G08

5ns/DIV

3468 G09

10ns/DIV

15MHz

25MHz

6903 G07

20

0

–80

20MHz

Peak-to-Peak Jitter vs Frequency

Supply Current vs Output

Frequency

Output Resistance vs Supply

Voltage

FREQUENCY (MHz)

0.001

0.01

0.1

1

10

100

6903 G05

10

8

9

7

5

3

6

4

2

1

0

SUPPLY VOLTAGE (V)

3.5

4.5

2.5

3.0

4.0

5.0

5.5

6903 G06

60

50

40

30

20

10

0

FREQUENCY (MHz)

0.1

1

10

100

6903 G04

10

1

0.1

0.01