ICS280

TRIPLE PLL FIELD PROG. SPREAD SPECTRUM CLOCK SYNTHESIZER

EPROM CLOCK SYNTHESIZER

IDT® TRIPLE PLL FIELD PROG. SPREAD SPECTRUM CLOCK SYNTHESIZER

4

ICS280

REV G 030212

The ICS280 operates in both center spread and down

spread modes. For center spread, the frequency can be

modulated between ±0.125% to ±2.0%. For down spread,

the frequency can be modulated between -0.25% to -4.0%.

Both output frequency banks will utilize identical spread

spectrum percentage deviations and modulation rates, if a

common VCO frequency can be identified.

Spread Spectrum Modulation Rate

The spread spectrum modulation frequency applied to the

output clock frequency may occur at a variety of rates. For

applications requiring the driving of “down-circuit” PLLs,

Zero Delay Buffers, or those adhering to PCI standards, the

spread spectrum modulation rate should be set to 30-33

kHz. For other applications, a 120 kHz modulation option is

available.

Absolute Maximum Ratings

Stresses above the ratings listed below can cause permanent damage to the ICS280. These ratings, which are

standard values for IDT commercially rated parts, are stress ratings only. Functional operation of the device at these

or any other conditions above those indicated in the operational sections of the specifications is not implied.

Exposure to absolute maximum rating conditions for extended periods can affect product reliability. Electrical

parameters are guaranteed only over the recommended operating temperature range.

Recommended Operation Conditions

Parameter

Condition

Min.

Typ.

Max.

Units

Supply Voltage, VDD

Referenced to GND

7

V

Inputs

Referenced to GND

-0.5

VDD+0.5

V

Clock Outputs

Referenced to GND

-0.5

VDD+0.5

V

Storage Temperature

-65

150

° C

Soldering Temperature

Max 10 seconds

260

° C

Junction Temperature

125

° C

Parameter

Min.

Typ.

Max.

Units

Ambient Operating Temperature (ICS280PG/PGLF)

0

+70

° C

Ambient Operating Temperature (ICS280PGI/PGILF)

-40

+85

° C

Power Supply Voltage (measured in respect to GND)

+3.135

+3.3

+3.465

V

Power Supply Ramp Time

4

ms