MK3233
Handheld System Clock Synthesizer
ICR O CLOC K
Description
Features
• Input crystal frequency of 32.768 kHz
• Lowest power solution available
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.
• 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
The device has multiple power down modes for the
CPU, communications, and 32.768 kHz clocks.
• 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)
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.
• Packaged in 16 pin narrow SOIC
Block Diagram
VDD GND
CPUS0
CPUS1
CPUS2
CPU
Output
Buffer
Clock Synthesis
and Control
Circuitry
CPUCLK
PDCPU
PDCOMM
PD
Communications
Clock Synthesis
and Control
Output
Buffer
1.843 or
3.686 MHz
VDD32
Circuitry
32.768 kHz
crystal
or
X1
Crystal
Oscillator
clock
Output
Buffer
32.768 kHz
X2
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