ICS307-01 Datasheet, PDF (3/9 Pages) Integrated Circuit Systems – 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:
To determine the best combination of VCO, reference,
and output dividers, see the online calculator at
http://www.icst.com/products/ics307inputForm.html or
contact ICS by sending an e-mail to [e-mail]
with the desired input crystal or clock and the desired
output frequency.
CLK1Frequency = InputFrequency ⋅ 2 ⋅ ₍---_R-----_D--^V--_W--^D-----^W₊-----₂--⁺--₎---⁸-_â‹---_O-----_D--
Where:
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
The following operating ranges should be observed.
For the commercial temperature range:
55MHz < InputFrequency ⋅ 2 ⋅ _{R-V----DD-----WW-------++-----82--} < 400MHz
200kHz < -^I--ⁿ---^p----^u-_R---^t--^FD----^r-_W-^e----^q--₊-^u----_2e----ⁿ---^c----^y-
And for the industrial temperature range:
60MHz < InputFrequency ⋅ 2 ⋅ _{R-V----DD-----WW-------++-----82--} < 360MHz
200kHz < ^{I--n----p---u-R--t--D--F---Wr--e----q-+--u---2e----n---c---y-}
MDS 307-01/02 F
3
Revision 121304
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