I C R O
C
LOC K
Description
The MK3233 is the smallest size, lowest power system
clock synthesizer available. It is the ideal way to
generate clocks for smart cell phones, PDAs, and other
devices where low power is required. Using analog
Phase-Locked Loop (PLL) techniques, the device
operates from a single 32.768 kHz crystal to produce
the 32.768 kHz, CPU, and serial communications
output clocks.
The device has multiple power down modes for the
CPU, communications, and 32.768 kHz clocks.
The MK3233 can save board space and cost even if it
only replaces the 32 kHz oscillator circuitry and one
additional surface mount crystal or oscillator. The
extremely low IDD, the ease of surface mounting, the
upgradeability of CPU frequencies, and the power
down capability are added benefits in using the part.
MK3233
Handheld System Clock Synthesizer
Features
• Input crystal frequency of 32.768 kHz
• Lowest power solution available
• Operating temperature of -20 to 70 °C
• Output clock frequencies up to 50 MHz
• Three output clocks
• 3.3 V or 5.0 V operation
• Duty cycle of 45/55
• Eight selectable CPU frequencies
• CPU or Communication clock power down
• Separate battery supply pin for 32 kHz runs to 2V
• IDD less than 4µA when 32 kHz running
• Serial port clocks of 1.8432 MHz (-01 version) or
3.6864 MHz (-02 version)
• Packaged in 16 pin narrow SOIC
Block Diagram
VDD
GND
CPUS0
CPUS1
CPUS2
PDCPU
CPU
Clock Synthesis
and Control
Circuitry
Output
Buffer
CPUCLK
PDCOMM
PD
VDD32
32.768 kHz
crystal
X1
or
clock
X2
Communications
Clock Synthesis
and Control
Circuitry
Output
Buffer
1.843 or
3.686 MHz
Crystal
Oscillator
Output
Buffer
32.768 kHz
MDS 3233 F
1
Revision 11070
Printed 11/16/00
Integrated Circuit Systems, Inc.• 525 Race Street• San Jose • CA • 95126• (408) 295-9800 tel • www.icst.com
ICS [ INTEGRATED CIRCUIT SYSTEMS ]
