June 2006
rev 0.1
Pin Configurations
XIN
1
8
7
ASM3P2187A/B
VDD
ModOUT
VSS
REFOUT
XOUT
2
SSON
3
ASM3P2187A
6
5
SEL
4
XIN
1
8
7
VDD
ModOUT
VSS
REFOUT
XOUT
2
ASM3P2187B
PDB
3
6
5
SEL
4
Pin Description
Pin#
1
2
3
4
Pin Name
XIN
XOUT
SSON / PDB*
SEL
Type
I
O
I
I
Description
Crystal connection or external reference frequency input. This pin has dual
functions. It can be connected either to an external crystal or an external reference
clock.
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.
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PULSECORE [ PulseCore Semiconductor ]
