General Description

The 843034 is a general purpose, low phase noise

LVPECL synthesizer which can generate frequencies for a

wide variety of applications. The 843034 has a 4:1 input

Multiplexer from which the following inputs can be

selected: one differential input, one single-ended input, or

two crystal oscillators, thus making the device ideal for

frequency translation or frequency generation. Each

differential LVPECL output pair has an output divider

which can be independently set so that two different

frequencies can be generated. Additionally, each LVPECL

output pair has a dedicated power supply pin so the

outputs can run at 3.3V or 2.5V. The 843034 also supplies

a buffered copy of the test clock or crystal frequency on

the single-ended REF_OUT output pin which can be

enabled or disabled, (disabled by default). The output

frequency can be programmed using either a serial or

parallel programming interface.

The phase jitter of the 843034 is less than 1ps RMS, making it

suitable for use in Fiber Channel, SONET, and Ethernet applications.

Features

• Dual differential 3.3V LVPECL outputs which can be set

independently for either 3.3V or 2.5V

• 4:1 Input Mux:

One differential input

One single-ended input

Two crystal oscillator interfaces

• CLK, nCLK pair can accept the following differential input levels:

LVPECL, LVDS, LVHSTL, HCSL

• TEST_CLK accepts LVCMOS or LVTTL input levels

• Output frequency range: 35MHz to 625MHz

• Crystal input frequency range: 12MHz to 40MHz

• VCO range: 560MHz to 750MHz

• Parallel or serial interface for programming feedback divider and

output dividers

• RMS phase jitter at 333.3MHz, using a 22.222MHz crystal (12kHz

to 20MHz): 0.91ps (typical)

• Supply voltage modes:

LVPECL outputs

Core/ Output

3.3V/ 3.3V

3.3V/ 2.5V

REF_OUT output

Core/ Output

3.3V/ 3.3V

• 0°C to 70°C ambient operating temperature

• Industrial temperature available upon request with ePad option

• Lead-free (RoHS 6) packaging