
W530-02
Document #: 38-07190 Rev. *A
Page 2 of 8
Pin Definitions
Overview
The W530-02 product is one of a series of devices in the
Cypress PREMIS family. The PREMIS family incorporates the
latest advances in phase-locked loop (PLL) spread spectrum
frequency synthesizer techniques. By frequency modulating
the output with a low frequency carrier, peak EMI is greatly
reduced. Use of this technology allows systems to pass
increasingly difficult EMI testing without resorting to costly
shielding or redesign.
Note:
1.
Pins that are marked with [*] have internal pull-up resistors. Pins that are marked with [^] have internal pull-down resistors.
In a system, not only is EMI reduced in the various clock lines,
but also in all signals which are synchronized to the clock.
Therefore, the benefits of using this technology increase with
the number of address and data lines in the system. The
Simplified Block Diagram on page 1 shows a simple imple-
mentation.
W
20
19
18
17
16
1
2
3
4
5
6
7
8
9
10
X1
X2
AVDD
MW0^
STOP^
OR1^
NC
GND
REFOUT
VDD
GND
IR1*
IR2*
SSOUT
MW1*
GND
14
13
15
11
12
VDD
MW2^
OR2*
SSON#
Simplified Block Diagram
Pin Configuration
[1]
SSOP
Spread Spectrum
Output
W530-02
(EMI suppressed)
3.3V or 5.0V
Oscillator or
Reference Input
Spread Spectrum
W530-02
(EMI suppressed)
3.3V or 5.0V
Input
X1
X2
X1
Pin Name
SSOUT
Pin No.
15
Pin Type
O
Pin Description
Output Modulated Frequency
. Frequency modulated signal. Frequency of the output is
selected as shown in
Table 1
.
Non-modulated Output
. This pin provides a copy of the reference frequency. This output
will not have the Spread Spectrum feature 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 external reference
signal, 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 the 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 (see
Table 2
). MW0: DOWN, MW1: UP, MW2: DOWN.
Reference Frequency Selector
. The 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.
No Connection
. Leave this pin unconnected.
Output Disable
. When pulled HIGH, stops all outputs at logic low voltage level. This pin has
an internal pull-down.
Output Frequency Selection Bits
. These pins select the frequency of operation for the
output. Refer to
Table 1
. OR1: DOWN, OR2: UP.
Power Connection
. Connected to 3.3V or 5V power supply.
Ground Connection
. Connect all ground pins to the common ground plane.
REFOUT
20
O
CLKIN or X1
1
I
NC or X2
2
I
SSON#
10
I
MW0:2
4, 14, 11
I
IR1:2
17,16
I
NC
STOP
7
5
NC
I
OR1:2
6,9
I
VDD
GND
3, 12, 19
8, 13, 18
P
G