W245-30 Datasheet, PDF (2/12 Pages) Cypress Semiconductor – Frequency Multiplying, Peak Reducing EMI Solution

W245-30
Pin Description
Pin Name
SSOUT
REFOUT
Pin No.
15
20
X1
1
X2
2
SSON#
10
MW0:2
4, 11, 14
IR1:2
17, 16
OR1:2
SCLK
SData
VDD
AVDD
GND
6, 9
7
5
12, 19
3
8, 13, 18
Pin
Type
O
O
I
I
I
I
I
I
I
I/O
P
P
G
Pin Description
Output Modulated Frequency: Frequency modulated copy of the input clock
(SSON# asserted).
Non-Modulated Output: This pin provides a copy of the reference frequency.
This output will not have the Spread Spectrum feature enabled regardless of
the state of logic input SSON#.
Crystal Connection or External Reference Frequency Input: This pin has
dual functions. It may either be connected to an external crystal, or to an
external reference clock.
Crystal Connection: Input connection for an external crystal. If using an ex-
ternal reference, this pin must be left unconnected.
Spread Spectrum Control (Active LOW): Asserting this signal (active LOW)
turns the internal modulation waveform on. This pin has an internal pull-down
resistor.
Modulation Width Selection: When Spread Spectrum feature is turned on,
these pins are used to select the amount of variation and peak EMI reduction
that is desired on the output signal. MW1:Down, MW1:Up, MW2:Down (See
Table 2).
Reference Frequency Selection: Logic level provided at this input indicates
to the internal logic what range the reference frequency is in and determines
the factor by which the device multiplies the input frequency. Refer to Table 3.
These pins have internal pull-up resistors.
Output Frequency Selection Bits: These pins select the frequency operation
for the output. Refer to Table 1. OR2 pin have internal pull-up resistors. OR1
pin have internal pull-down resistors.
Clock pin for SMBus circuitry.
Data pin for SMBus Circuitry.
Power Connection: Connected to 3.3V or 5V power supply.
Analog Power Connection: Connected to 3.3V or 5V power supply.
Ground Connection: Connect all ground pins to the common ground plane.
Document #: 38-07229 Rev. *B
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