ics307 Integrated Device Technology, ics307 Datasheet - Page 3

• Manufacturer Part Number: ics307
• Description: Serially Programmable Clock Source
• Manufacturer: Integrated Device Technology

IDT™ / ICS™ SERIALLY PROGRAMMABLE CLOCK SOURCE
ICS307-01/-02
SERIALLY PROGRAMMABLE CLOCK SOURCE
Determining the Output Frequency
On power-up, the ICS307-01 on-chip registers can have
random values so almost any frequency may be output
from the part. CLK1 will always have some clock signal
present, but CLK2 could possibly be OFF (low).
The ICS307-02 on-chip registers are initially configured
to provide a x1 output clock on both the CLK1 and CLK2
outputs. The output frequency will be the same as the
input clock or crystal. This is useful if the ICS307 will
provide the initial system clock at power-up. Since this
feature is an advantage in most systems, the
ICS307-02 is recommended for new designs.
With programming, the user has full control in changing
the desired output frequency to any value over the
range shown in Table 1 on page 4. The output of the
ICS307 can be determined by the following equation:
The following operating ranges should be observed. For
the commercial temperature range:
CLK1Frequency
Where:
55MHz InputFrequency 2
200kHz
VCO Divider Word (VDW) = 4 to 511 (0, 1, 2, 3
are not permitted)
Reference Divider Word (RDW) = 1 to 127 (0 is
not permitted)
Output Divider = values on page 4
<
<
InputFrequency
--------------------------------------------- -
=
RDW
InputFrequency 2
+
2
⋅
⋅
VDW
------------------------
RDW
⋅
+
+
⋅
------------------------------------------ -
(
8
2
RDW
<
VDW
400MHz
+
2
+
) OD
8
⋅
3
And for the industrial temperature range:
To determine the best combination of VCO, reference,
and output dividers, see the online calculator at
http://www.icst.com/products/ics307inputForm.html
contact ICS by sending an e-mail to [e-mail]
with the desired input crystal or clock and the desired
output frequency.
60MHz InputFrequency 2
200kHz
<
<
Input Frequency
------------------------------------------ -
RDW
+
SER PROG CLOCK SYNTHESIZER
2
⋅ ⋅
VDW
------------------------
RDW
ICS307-01/-02 REV G 031606
+
+
8
2
<
360MHz
or