W181 Cypress Semiconductor, W181 Datasheet - Page 2

• Manufacturer Part Number: W181
• Description: Peak Reducing EMI Solution
• Manufacturer: Cypress Semiconductor

Pin Definitions
CLKOUT
CLKIN or X1
NC or X2
SSON#
FS1:2
SS%
VDD
GND
NC
Pin Name
8(02/03/52/
7, 8 (01/51)
Pin No.
(SOIC)
53)
5
1
2
4
6
3
5, 7, 9, 11, 13,
(TSSOP)(-01)
Pin No.
12, 1
14
10
8
2
3
--
6
4
Type
Pin
NC
O
G
P
I
I
I
I
I
2
Output Modulated Frequency: Frequency modulated copy
of the unmodulated input clock (SSON# asserted).
Crystal Connection or External Reference Frequency In-
put: This pin has dual functions. It may either be connected
to an external crystal, or to an external reference clock.
Crystal Connection: If using an external reference, this pin
must be left unconnected.
Spread Spectrum Control (Active LOW): Asserting this sig-
nal (active LOW) turns the internal modulation waveform on.
This pin has an internal pull-down resistor.
Frequency Selection Bit(s) 1 and 2: These pins select the
frequency range of operation. Refer to Table 2. These pins
have internal pull-up resistors.
Modulation Width Selection: When Spread Spectrum fea-
ture is turned on, this pin is used to select the amount of
variation and peak EMI reduction that is desired on the output
signal. This pin has an internal pull-up resistor.
Power Connection: Connected to 3.3V or 5V power supply.
Ground Connection: Connect all ground pins to the com-
mon system ground plane.
No Connection.
Pin Description
W181