PRELIMINARY

XRK69773

1:12 LVCMOS PLL CLOCK GENERATOR

APRIL 2006

REV. P1.0.0

GENERAL DESCRIPTION

The XRK69773 is a PLL based LVCMOS Clock Generator

targeted for high performance and low skew clock distribu-

tion applications. The XRK69773 can select between one

of three reference inputs and provides 14 LVCMOS outputs

-12 outputs (3 banks of 4) for clock distribution, 1 for feed-

back and 1 for synchronization.

The XRK69773 is a highly flexible device. It has 3 select-

able inputs, (one differential and two single-ended inputs) to

support system clock redundancy. Up to three different

clock frequencys can be generated and outputted on the

three output banks. Switching the internal reference clock

is controlled by the control input, CLK_SEL.

The XRK69773 uses PLL technology to frequency lock its

outputs to the input reference clock. The divider in the feed-

back path will determine the frequency of the VCO. Each of

the separate output banks can individually divide down the

VCO output frequency. This allows the XRK69773 to gen-

erate a multitude of different bank frequency ratios and out-

put-to-input frequency ratios.

The outputs of the XRK69773 can individually be immobi-

lized, in the low state, by use of the clock stop feature. All

outputs except QC0 and QFB can be immobilized through a

2 pin serial interface. Global output disabling and reset can

be achieved the control input MR/OE.

The XRK69773 also has a QSYNC output which can be

used for system synchronization purposes. It monitors

Bank A and Bank C outputs and goes low one period of the

faster clock prior to coincident rising edges of Bank A and

Bank C clocks. QSYNC then goes high again when the

coincident rising edges of Bank A and Bank C occur. This

feature is used primarily in applications where Bank A and

Bank C are running at different frequencies, and is

particularly useful when they are running at non-integer

multiples of one another.

The XRK69773 has an output frequency range of 8.33MHz

to 240MHz and an input frequency range of 5MHz to

120MHz.

FEATURES

reference clock source

■

3 banks with 4 outputs each. Frequencies can

be individually controlled by bank

■

1 dedicated feedback with frequency control

■

1 Sync

APPLICATIONS

PRODUCT ORDERING INFORMATION

XRK69773CR

52-LEAD LQFP

0°C to +70°C

XRK69773IR

52-LEAD LQFP

-40°C to +85°C