ICS844004I-04 Datasheet, PDF (2/13 Pages) Integrated Circuit Systems – FEMTOCLOCKS™ CRYSTAL/LVCMOS-TO-LVDS FREQUENCY SYNTHESIZER

Integrated
Circuit
Systems, Inc.
PRELIMINARY
ICS844004I-04
FEMTOCLOCKS™ CRYSTAL/LVCMOS-TO-
LVDS FREQUENCY SYNTHESIZER
TABLE 1. PIN DESCRIPTIONS
Number Name
Type
Description
1, 2
nQ1, Q1 Output
Differential output pair. LVDS interface levels.
3, 22
4, 5
6
7,
10,
12,
18
V_DDO
Q0, nQ0
MR
F_SEL3,
F_SEL0,
F_SEL1,
F_SEL2
Power
Ouput
Input
Output supply pins.
Differential output pair. LVDS interface levels.
Pulldown
Active HIGH Master Reset. When logic HIGH, the internal dividers are
reset causing the true outputs Qx to go low and the inverted outputs nQx
to go high. When logic LOW, the internal dividers and the outputs are
enabled. LVCMOS/LVTTL interface levels.
Input Pullup Frequency select pins. LVCMOS/LVTTL interface levels. See Table 3.
8
nc
Unused
No connect.
9
11
13, 14
V
DDA
V_DD
XTAL_OUT,
XTAL_IN
Power
Power
Input
Analog supply pin.
Core supply pin.
Parallel resonant crystal interface. XTAL_OUT is the output,
XTAL_IN is the input.
15, 19
GND
Power
Power supply ground.
16
CLK
Input Pulldown LVCMOS/LVTTL clock input.
Selects between crystal or CLK inputs as the the PLL Reference source.
17 INPUT_SEL Input Pulldown Selects XTAL inputs when LOW. Selects CLK when HIGH.
LVCMOS/LVTTL interface levels.
20, 21 nQ3, Q3 Output
Differential output pair. LVDS interface levels.
23, 24 Q2, nQ2 Output
Differential output pair. LVDS interface levels.
NOTE: Pulldown and Pullup refer to internal input resistors. See Table 2, Pin Characteristics, for typical values.
TABLE 2. PIN CHARACTERISTICS
Symbol
C_IN
R
PULLDOWN
R_PULLUP
Parameter
Input Capacitance
Input Pulldown Resistor
Input Pullup Resistor
Test Conditions
Minimum
Typical
4
51
51
Maximum
Units
pF
kΩ
kΩ
TABLE 3. OUTPUT CONFIGURATION AND FREQUENCY RANGE FUNCTION TABLE
Inputs
F_SELx XTAL (MHz)
0
19.44
1
19.44
0
18.75
VCO
(MHz)
622.08
622.08
600
N Divider Value
N0:N3
1
4
1
Output Frequency (MHz)
Q0/nQ0:Q3/nQ3
622.08
155.52
600
1
18.75
600
4
150
0
19.53125
625
1
625
1
19.53125
625
4
156.25
0
20.141601 644.5312
1
644.5312
1
20.141601 644.5312
4
161.13
Application
SONET/SDH
SATA
10 Gigabit Ethernet
10 Gigabit Ethernet
66B/64B FEC
844004AGI-04
www.icst.com/products/hiperclocks.html
2
REV. A JANUARY 26, 2006