General Description
The 844003-01 is a 3 differential output LVDS Synthesizer
designed to generate Ethernet refer- ence clock frequencies.
Using a 19.53125MHz or 25MHz, 18pF parallel resonant crystal,
the following frequencies can be generated based on the settings
of 4 frequency select pins (DIV_SELA[1:0], DIV_SELB[1:0]):
625MHz, 312.5MHz, 156.25MHz, and 125MHz. The 844003-01
has 2 output banks, Bank A with 1 differential LVDS output pair
and Bank B with 2 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 844003-01 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 844003-01 is
packaged in a small 24-pin TSSOP package.

Features
• Three differential LVDS output pairs on two banks, Bank A with
one LVDS pair and Bank B with two LVDS output pairs
• Using a 19.53125MHz or 25MHz crystal, the two output banks
can be independently set for 625MHz, 312.5MHz, 156.25MHz
or 125MHz
• Selectable crystal oscillator interface or LVCMOS/LVTTL
single-ended input
• VCO range: 490MHz - 680MHz
• RMS phase jitter @ 156.25MHz (1.875MHz – 20MHz):
0.56ps (typical)
• Full 3.3V supply mode
• 0°C to 70°C ambient operating temperature
• Available in lead-free (RoHS 6) package