November 2003
rev 1.1
ASM5P23SS08A
3.3V Zero Delay Buffer
be driven to FBK pin, and can be obtained from one of the
outputs. The input-to-input propogation delay is guaranteed
to be less than 350ps, and the output-to-output skew is
guaranteed to be less than 250ps.
General Features
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Zero input - output propagation delay, adjustable by
capacitive load on FBK input.
EMI reduced output with on-chip EMI reduction
capability.
Multiple configurations
Configurations Table”.
The ASM5P23SS08A has two banks of four outputs each,
which can be controlled by the select inputs as shown in
the Select Input Decoding Table. If all the output clocks are
not required, Bank B can be three-stated. The select input
also allows the input clock to be directly applied to the
outputs for chip and system testing purposes.
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Refer “ASM5P23SS08A
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Input frequency range : 10MHz to 133MHz
Multiple low-skew outputs.
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Output-output skew less than 200 ps.
Device-device skew less than 700 ps.
Two banks of four outputs, three-stateable by two
select inputs.
Multiple ASM5P23SS08A devices can accept the same
input clock and distribute it. In this case the skew between
the outputs of the two devices is guaranteed to be less than
700ps.
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Less than 200 ps cycle-to-cycle jitter (-1, -1H, -4, -5H).
Available in 16-pin SOIC and TSSOP packages.
3.3V operation.
Advanced 0.35µ CMOS technology.
Industrial temperature available.
The ASM5P23SS08A is available in five different
configurations (Refer “ASM5P23SS08A Configurations
Table). The ASM5P23SS08A-1 is the base part, where the
output frequencies equal the reference if there is no
counter in the feedback path. The ASM5P23SS08A-1H is
the high-drive version of the -1 and the rise and fall times
on this device are much faster.
Functional Description
ASM5P23SS08A is a versatile, spread spectrum output,
3.3V zero-delay buffer designed to distribute high-speed
clocks with EMI supression capability. It is available in a
16-pin package. The ASM5P23SS08A family incorporates
the latest advances in PLL spread spectrum techniques to
greatly reduce the peak EMI by modulating the output
The ASM5P23SS08A-2 allows the user to obtain 2X and
1X frequencies on each output bank. The exact
configuration and output frequencies depends on which
output drives the feedback pin. The ASM5P23SS08A-3
allows the user to obtain 4X and 2X frequencies on the
outputs.
frequency with
a
low frequency carrier
.
The
ASM5P23SS08A allows significant system cost savings by
reducing the number of circuit board layers and shielding
that are traditionally required to pass EMI regulations.
Because the modulating frequency is typically 1000 times
slower than the fundamental clock, the spread spectrum
process has negligible impact on system performance
while giving significant cost savings. Alliance offers options
with different spreading patterns with more spread and
greater EMI reduction.
The ASM5P23SS08A-4 enables the user to obtain 2X
clocks on all outputs. Thus, the part is extremely versatile,
and can be used in a variety of applications.
The ASM5P23SS08A-5H is a high-drive version with
REF/2 on both banks.
The part has an on-chip PLL whick locks to an input clock
presented on the REF pin. The PLL feedback is required to
Alliance Semiconductor
2575, Augustine Drive • Santa Clara, CA • Tel: 408.855.4900 • Fax: 408.855.4999 • www.alsc.com
Notice: The information in this document is subject to change without notice.