May 2008
rev 0.2
Pin Configurations
ASM3P2187A/B
CLKIN/ XIN
1
8
7
VDD
ModOUT
VSS
REFOUT
XOUT
2
ASM3P2187A
SSON
3
6
5
SEL
4
CLKIN/ XIN
1
XOUT
2
ASM3P2187B
PDB
3
8
7
6
5
VDD
ModOUT
VSS
REFOUT
SEL
4
Pin Description
Pin#
1
2
3
4
Pin Name
CLKIN/XIN
XOUT
SSON / PDB*
SEL
Type
I
O
I
I
Description
External reference Clock input or Crystal connection.
Crystal connection. If using an external reference, this pin must be left
unconnected.
Modulation enable pin/ Power down pin. Has an Internal pull up resistor
Modulation rate setting pin
Centre spread, SEL = “L” : Frequency Deviation ± 0.5%
Centre spread, SEL = “H” : Frequency Deviation ± 1.0%
Has an Internal pull up resistor.
5
6
7
8
REFOUT
VSS
ModOUT
VDD
O
P
O
P
Non-modulated clock output pin. The Frequency is same as input
frequency. This pin becomes to “L” at power-down.
Ground Connection. Connect to system ground.
Modulated clock output pin
This pin becomes to“L” at power-down.
Power Supply Voltage Pin. Connect to +3.3V.
* SSON Pin is available in ASM3P2187A Device and PDB Pin is available in ASM3P2187B Device
Spread Spectrum Clock Generator for Mobile Applications
Notice: The information in this document is subject to change without notice.
2 of 9
PULSECORE [ PulseCore Semiconductor ]
