ICS300/ICS301/ICS302
QTClock™ Quick Turn Clock Synthesizer
Pin Assignments
X1/ICLK
VDD
GND
REF
GND
VDD
GND
REF
8
1
2 ICS300 7
3 ICS301 6
4
5
1
2 ICS302
3
4
8
7
6
5
X2
PDTS
DC
CLK
ICLK
PDTS
DC
CLK
REF Clock Options
REF
Reference
Reference/2
CLK/2
Off
Comments
Buffered oscillator output
Oscillator frequency divided by two
CLK frequency divided by two
Output stopped low. Lowest jitter
Pin Descriptions
Number Number Name
Type Description
300/1
302
1
8
X1/ICLK
I
Crystal connection or clock input. Clock only on ICS302.
2
2
VDD
P Connect to +3.3V or +5V.
3
1, 3
GND
P Connect to ground.
4
4
REF
O Buffered crystal oscillator output clock, or variation per REF clock options table above.
5
5
CLK
O Clock output. Fixed frequency between 6 and 200 MHz programmed at factory.
6
6
DC
-
Don't Connect anything to this pin.
7
7
PDTS
I
Powers down PLL, and puts both outputs into high impedance state, when low.
8
-
X2
O Crystal connection. Leave unconnected for clock input.
Key: I = Input, O = output, P = power supply connection
Device Configuration
The specification is complete when the ICS300/301/302 QTClock Order Form accompanies this data
sheet. The order form lists the input, REF, and CLK actual frequencies, as well as any other available
options. This unique configuration is given a two character alphanumeric programming code, which must
be specified when referring to samples.
External Components / Crystal Selection
The ICS300/301/302 requires a 0.01µF decoupling capacitor to be connected between VDD and GND.
It must be connected close to the ICS300/301/302 to minimize lead inductance. No external power
supply filtering is required for this device. A 33Ω terminating resistor can be used next to the CLK and
REF pins. The total on-chip capacitance is approximately 16 pF, so a parallel resonant, fundamental mode
crystal should be used. For crystals with a specified load capacitance greater than 16 pF, crystal capacitors
can be connected from each of the pins X1 and X2 to Ground. The value (in pF) of these crystal caps
should be = (CL -16)*2, where CL is the crystal load capacitance in pF. These external capacitors are only
required for applications where the exact frequency is critical. For a clock input, connect to X1/ICLK and
leave X2 unconnected (no capacitors on either).
MDS 300QT E
2
Revision 111000
Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA•95126•(408) 295-9800tel• www.icst.com
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