11

SY89531L

Micrel, Inc.

M9999-110405

hbwhelp@micrel.com or (408) 955-1690

Power Supply Filtering Techniques

As with any high-speed integrated circuit, power supply

filtering is very important. At a minimum, V

and all V

via to the power supply plane, and separate bypass

capacitors should be used for each pin. To achieve optimal

jitter performance, each power supply pin should use

separate instances of the circuit shown in Figure 4.

use ferrite bead = 200mA, 0.45

Ω DC,

Murata P/N BLM21A1025

Ω DC,

Murata, P/N BLM31P005

*Component size: 0805

1

µF

22

µF

0.01

µF

Ferrite Bead*

“Power Supply”

side

“Device”

side

Pins

Figure 4. Power Supply Filtering

Output Logic Characteristics

See

“Output Termination Recommendations” for

illustrations. In cases where single-ended output is desired,

the designer should terminate the unused complimentary

output in the same manner as the normal output that is

begin used. Unused output pairs can be left floating. Unused

output banks can be switched off by tying the appropriate

FSEL pins to ground. Unused output pairs that are in a

bank that is disabled can be left floating, regardless of output

driver type.

LVPECL operation:

• Typical voltage swing is 700mV

50

Ω.

• Common mode voltage is V

• 100

Ω termination across the output pair is NOT

recommended for LVPECL.

HSTL operation (Bank B):

• Typical voltage swing is 250mV

effective 50

Ω.

Thermal Considerations

This part has an exposed die pad for enhanced heat

dissipation. We strongly recommend soldering the exposed

pad to a ground plane. Where this is not possible, we

recommend maintaining at least 500lfpm air flow.

For additional information on exposed-pad characteristics

and implementation details, see Amkor Technology’s write-

up at www.amkor.com.

Output Divider

0

0

0

Output Disable Function, all outputs: Q = LOW, /Q = HIGH

0

0

1

VCO

÷ 2

0

1

0

VCO

÷ 4

0

1

1

VCO

÷ 6

1

0

0

VCO

÷ 8

1

0

1

VCO

÷ 10

1

1

0

VCO

÷ 12

1

1

1

VCO

÷ 18

POST-DIVIDE FREQUENCY SELECT TABLE (FSEL)

Note 1. Same dividers apply to FSEL_B (0:2) and FSEL_C (0:2).