General Description

The 844003I-04 is a 3 differential output LVDS Synthesizer designed

to generate Ethernet reference clock frequencies. Using a

19.44MHz, 20MHz or 25MHz, 18pF parallel resonant crystal, the

following frequencies can be generated based on the settings of four

frequency select pins (DIV_SELA[1:0], DIV_SELB[1:0]): 625MHz,

622.08MHz, 312.5MHz, 250MHz, 156.25MHz, 125MHz and

100MHz. The 844003I-04 has two output banks, Bank A with one

differential LVDS output pair and Bank B with two differential LVDS

output pairs.

The two banks have their own dedicated frequency select pins and

can be independently set for the frequencies mentioned above. The

844003I-04 uses IDT’s 3RD generation low phase noise VCO

technology and can achieve 1ps or lower typical rms phase jitter,

easily meeting Ethernet jitter requirements. The 844003I-04 is

packaged in a 32-pin VFQFN package.

Features

• Three LVDS outputs on two banks, Bank A with one LVDS pair

and Bank B with 2 LVDS output pairs

• Using a 19.44MHz, 20MHz, or 25MHz crystal, the two output

banks can be independently set for 625MHz, 622.08MHz,

312.5MHz, 250MHz, 156.25MHz, 125MHz or 100MHz

• Selectable crystal oscillator interface or LVCMOS/LVTTL

single-ended input

• VCO range: 490MHz to 680MHz

• RMS phase jitter at 125MHz (1.875MHz – 20MHz):

0.50ps (typical)

• Full 3.3V output supply mode

• -40°C to 85°C ambient operating temperature

• Available in lead-free (RoHS 6) package

• For functional replacement part use 8T49N241