Datasheet MK3230-01STR, MK3230-02S, MK3230-02STR, MK3230-01S Datasheet (ICST)

MK3230

ICRO

C

LOCK

Description

The MK3230 is the smallest size, lowest power system
clock synthesizer available. It is the ideal way to
generate clocks for portable computers, 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 32.768kHz, CPU, system, keyboard
controller, and floppy (or super I/O) controller output
clocks.

The device has two power down modes. From the CPU
decoding table (when FS0, FS1, and FS2 all are low),
the CPU and 14.3 MHz system clocks can be turned
off. Also, the keyboard and 24 MHz peripheral clocks
can be shut off from PD24+KBD (pin 10). The part has
a separate VDD32 pin for the 32 kHz clock, allowing
it to run at a different voltage (down to 2.0V) from the
rest of the chip, allowing it to run from a back-up
battery.

Block Diagram

Portable System Clock Synthesizer

Features

• Packaged in 16 pin narrow (0.150”) SOIC

• Input crystal frequency of 32.768 kHz

• Lowest power solution available

• Lowest profile clock solution where height is critical

• Output clock frequencies up to 80 MHz

• Five output clocks

• 3.3V or 5.0V operation

• Duty cycle of 45/55

• Seven selectable CPU frequencies

• CPU and peripheral clock power downs

• Separate battery supply pin for 32 kHz

• IDD less than 5µA when 32 kHz running

• Available with either 12MHz (-01) or 16MHz (-02)
keyboard clock output

• 14.3MHz output is not suitable for driving PLL for
CRT. Will drive all other functions

• 32kHz crystals require long startup (>500ms)

CPUS0
CPUS1

CPUS2

PD24+KBD

VDD32

X1

X2

VDD

GND

Crystal

Oscillator

Clock Synthesis

and Control

Circuitry

Output

Buffer

Output

Buffer

Output

Buffer

Output

Buffer

Output

Buffer

CPUCLK

12 or 16 MHz

24.00 MHz

14.32 MHz

32.768 kHz

32.768 kHz
crystal

MDS 3230 F 1 Revision 022798 Printed 11/16/00

Integrated Circuit Systems, Inc.•525 Race Street•San Jose•CA•95126•[phone]tel•www.icst.com

MK3230

Portable System Clock Synthesizer

CPU Clock Decoding

CPUS2 CPUS1 CPUS0 CPUCLK (MHz)

0 0 0 Off+14M off
0 0 1 80.00
0 1 0 25.00
0 1 1 66.66
1 0 0 20.00
1 0 1 50.00
1 1 0 33.33
1 1 1 4.00

Pin Assignment

CPUS2

VDD32

VDD
GND

24M

ICRO

X2
X1

C

LOCK

1

2
3

4
5

6

16

15
14
13
12
11

7 10

CPUS1
CPUS0
CPUCLK

VDD
GND

14.3M
PD24+KBD

Frequency transitions (except going to/from

32K

8 9

KBOUT

off) will occur smoothly, and are compatible
with all 486 processors.

Pin Descriptions

Number Name Type Description

1 CPUS2 I Select 2 for CPUCLK frequencies. See Table above.
2 X2 O Crystal connection. Connect to 32.768 kHz crystal.
3 X1 I Crystal connection. Connect to 32.768 kHz crystal.
4 VDD32 P Separate power supply connection for 32.768kHz clock. Will operate to 2.0V.
5 VDD P Connect to +3.3V or +5V. Must be the same voltage as pin 13.
6 GND P Connect to ground.
7 24M O 24 MHz floppy (or super I/O) clock output.
8 32K O 32.768 kHz square wave clock output.

9 KBOUT O Keyboard clock output. Either 12MHz (-01) or 16MHz (-02)
10 PD24+KBD I Power Down 24M+keyboard. Shuts off both clock outputs (pins 7,9) when low.
11 14.3M O 14.318 MHz system clock output. Do not drive a CRT PLL device with this output.
12 GND P Connect to ground.
13 VDD P Connect to +3.3V or +5V. Must be the same voltage as pin 5.
14 CPUCLK O CPUCLK output. See Table above.
15 CPUS0 I Select 0 for CPUCLK frequencies. See Table above.
16 CPUS1 I Select 1 for CPUCLK frequencies. See Table above.

Type: I = Input, O = output, P = power supply connection

Power Down status: Output clocks will stop in a low state when powered down

External Components

The MK3230 requires a minimum number of external components for proper operation. Decoupling
capacitors of 0.1µF should be connected between VDD and GND, and VDD32 and GND, as close to the
MK3230 as possible. A 10kΩ series resistor should be used to filter the VDD32 pin. A series termination
resistor of 33Ω may be used for each clock output. The device does not require (nor do we recommend)
capacitors connected to the crystal pins. The 32.768 kHz crystal must be connected as close to the chip as
possible. See Application Brief MAB02 for a discussion on tuning for use on a real time clock (RTC).

MDS 3230 F 2 Revision 022798 Printed 11/16/00

Integrated Circuit Systems, Inc.•525 Race Street•San Jose•CA•95126•[phone]tel•www.icst.com

MK3230

ABSOLUTE MAXIMUM RATINGS (note 1)

32.768kHz crystal with ESR ≤25kΩ

ICRO

C

LOCK

Portable System Clock Synthesizer

Electrical Specifications

Parameter Conditions Minimum Typical Maximum Units

Supply Voltage, VDD Referenced to GND 7 V
Inputs and Clock Outputs Referenced to GND -0.5 VDD+0.5 V
Ambient Operating Temperature 0 70 °C
Soldering Temperature Max of 30 seconds 260 °C
Storage Temperature -65 150 °C

DC CHARACTERISTICS

Operating Voltage, VDD 3.0 5.5 V
Operating Voltage,VDD32 2.0 5.5 V
Input High Voltage, VIH VDD=5V 2.0 V
Input Low Voltage, VIL VDD=5V 0.8 V
Output High Voltage, VOH VDD=5V, IOH=-25mA 2.4 V
Output Low Voltage, VOL VDD=5V, IOL=25mA 0.4 V
Input High Voltage, VIH VDD=3.3V 1.9 V
Input Low Voltage, VIL VDD=3.3V 0.4 V
Output High Voltage, VOH VDD=3.3V, IOH=-8mA 2.4 V
Output Low Voltage, VOL VDD=3.3V, IOL=8mA 0.4 V
IDD Operating Supply Current, 5V No Load, 80MHz 25 mA
IDD32 with only 32 kHz running, 5V No Load 3.5 µA
IDD Operating Supply Current, 3.3V No Load, 80MHz 15 mA
IDD32 with only 32 kHz running, 3.3V No Load 2.5 µA
Short Circuit Current, 5V 32 kHz output ±30 mA
Short Circuit Current, 5V Each MHz output ±100 mA
Input Capacitance 7 pF
Internal Crystal Capacitance Pins 2, 3 only 15 pF

AC CHARACTERISTICS

Input Frequency 32.768 kHz
Output Clock Rise and Fall Time, 0.2 to 0.8VDD 2 ns
Output Clock Duty Cycle, all MHz clocks At VDD/2 45 49 to 51 55 %

32.768 kHz Clock Duty Cycle At VDD32/2 57 %
Absolute Clock Period Jitter, CPU clock 25 to 80 MHz -500 500 ps
Power up time, CPU off to 80 MHz, 32k running VDD=3.3 or 5V 9 ms
Transition time, 4 MHz to 80 MHz VDD=3.3 or 5V 4 ms
Transition time, 80 MHz to 4 MHz VDD=3.3 or 5V 2.5 ms
Power on time,VDD32=0V to all clocks stable

Note 1: Stresses beyond those listed under Absolute Maximum Ratings could cause permanent damage to the device. Prolonged
exposure to levels above the operating limits but below the Absolute Maximums may affect device reliability.

500 750 ms

Note on the 14.32 MHz output : The actual output frequency from this clock is 14.3196 MHz, versus

14.31818 MHz that has been traditional. This output can be used as the input to digital chips providing
functions such as timing or keyboard, but it should NOT be used to drive a graphics PLL that is used for a
CRT display. Instead, use a 14.318MHz crystal as the input to the CRT graphics device.

MDS 3230 F 3 Revision 022798 Printed 11/16/00

Integrated Circuit Systems, Inc.•525 Race Street•San Jose•CA•95126•[phone]tel•www.icst.com

MK3230

Inches

Millimeters

ICRO

Input and Output Voltages
The MK3230 can operate with VDD = 3.0V to 5.5V, and VDD32 = 2.0V to 5.5V in any combination.

Both VDD pins (pin #5 and pin #13) must be connected to the same voltage.
The amplitude of the 32.768 kHz output clock will be equal to VDD32, and the amplitude of the MHz

clocks will be equal to VDD.
If using a clock input, the input voltage applied to X1 may not exceed VDD32, and the amplitude of any

other input may not exceed VDD. Consult MicroClock if your application is an exception to this.

C

LOCK

Package Outline and Package Dimensions

E H

h x 45°

Portable System Clock Synthesizer

16 pin SOIC narrow

Symbol Min Max Min Max

A 0.055 0.070 1.397 1.778
b 0.013 0.019 0.330 0.483

c 0.007 0.010 0.191 0.254

D 0.385 0.400 9.779 10.160

E 0.150 0.160 3.810 4.064

H 0.225 0.245 5.715 6.223

e

h 0.016 0.406

Q 0.004 0.01 0.102 0.254

D

Q

c

e

b

A

Ordering Information

Part/Order Number Marking Keyboard frequency Package Temperature

MK3230-01S MK3230-01S 12 MHz 16 pin SOIC 0-70°C
MK3230-02S MK3230-02S 16 MHz 16 pin SOIC 0-70°C

MK3230-01STR MK3230-01S 12 MHz Add Tape & Reel 0-70°C
MK3230-02STR MK3230-02S 16 MHz Add Tape & Reel 0-70°C

While the information presented herein has been checked for both accuracy and reliability, MicroClock Incorporated assumes no responsibility for either its use or for the
infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in
normal commercial applications. Any other applications such as those requiring extended temperature range, high reliability, or other extraordinary environmental requirements
are not recommended without additional processing by MicroClock. MicroClock reserves the right to change any circuitry or specifications without notice. MicroClock does not
authorize or warrant any MicroClock product for use in life support devices or critical medical instruments.

MDS 3230 F 4 Revision 022798 Printed 11/16/00

Integrated Circuit Systems, Inc.•525 Race Street•San Jose•CA•95126•[phone]tel•www.icst.com