Datasheet MK1422STR, MK1422S Datasheet (ICST)

MK1422

OPL3/4+Codec Portable Clock Source

Description

The MK1422 is the ideal way to generate clocks
for sound in portable computers. It provides clocks
for Analog Devices’ or Crystal Semiconductor’s
stereo codecs, and Yamaha’s OPL3L, OPL3LS,
and OPL4. The MK1422 uses either a

14.318 MHz crystal, or a 14.318 MHz bus clock
input to synthesize the clocks required to drive the
codec, and the 33.868 MHz required for the FM
or wavetable music synthesizer. It includes a power
down pin to save power without using a FET. In an
8 pin SOIC, the MK1422 can save component
count, board space, and cost over surface mount
crystals, and increase reliability by eliminating
three mechanical devices from the board.

MicroClock offers many other parts with stereo
codec support. MicroClock invented sound clocks,
and has the widest product offering and greatest
production experience on these devices. The
MK1422 is pin compatible with MicroClock’s
popular MK1420 when the 14.318MHz clock
output is not used. See the MK14223 for 3.3V.

Block Diagram

VDD GND

Features

• Packaged in 8 pin SOIC

• Input crystal or clock frequency of 14.318 MHz

• Output clock frequencies of 16.934 MHz,

24.576 MHz, and 33.868 MHz

• 25mA drive capability at TTL levels

• Advanced, low power CMOS process

• Low jitter ensures full 16 bit S/N ratio

• Insensitive to input clock duty cycle

• Power down for portable computers

AC Coupling/Portable Applications

For applications in portable computers, see the
MK14223, which is specified to operate at 3.3V. It
is possible to drive the MK1422 with a 3.3V,

14.318MHz clock by a.c. coupling using a 0.01µF
capacitor connected in series to the X1 pin. But the
operating VDD on pin 2 must be 5V±10%. This
technique is also effective if the input clock doesn’t
meet the VIH and VIL specifications on page 3.

Additional Clocks or Features

If more than these three output clocks or features
such as output enable are needed, MicroClock can
provide a quick turn modification for your custom
requirements.

All Chip
Power Down

14.318 MHz
crystal or clock

X1/ICLK

Crystal

Oscillator

X2

MDS 1422 B 1 Revision 080698 Printed 11/15/00

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

Clock Synthesis

Circuitry

Output

Buffer

Output

Buffer

Output

Buffer

16.934 MHz

24.576 MHz

33.868 MHz

Pin Assignment

MK1422

OPL3/4+Codec Portable Clock Source

Suggested Layout

14.318 MHz in

X1/ICLK

1 8

X2

V

Pin 1

2

8

7

0.1µF

VDD

GND

2

3

7

PD

3

6

33.9M

6

33Ω (optional)

16.9M

4

5

24.6M

33Ω (optional)

G

16.9MHz out

4

5

33Ω (optional)

24.6MHz out

Pin Descriptions

Number Name Type Description

1 X1/ICLK I Crystal Connection. Connect to a 14.318 MHz crystal or clock.
2 VDD P Connect to +5V.
3 GND P Connect to ground.
4 16.9M O 16.9344 MHz clock output for stereo codec.
5 24.6M O 24.576 MHz clock output for stereo codec.
6 33.9M O 33.868 MHz clock output for OPL4.
7 PD I Power Down. Shuts off entire chip when low. All clock outputs stop low.
8 X2 O Crystal Connection to a 14.318 MHz crystal, or leave unconnected for clock input.

PD

33.9MHz
out

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

External Components/Crystal Selection

A minimum number of external components are required for proper oscillation. For a crystal input, one
22pF load capacitor should be connected to each of the X1 and X2 pins and ground, and a parallel
resonant 14.318 MHz, 16pF load, crystal is recommended. Load capacitor values near these are acceptable,
as is a series resonant crystal, but either will result in frequencies which are further off of the target
frequency. For a clock input, connect to X1 and leave X2 unconnected. A decoupling capacitor of 0.1µF
should be connected between VDD and GND, and 33Ω terminating resistors may be used on the clock
outputs.

MDS 1422 B 2 Revision 080698 Printed 11/15/00

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

MK1422

ABSOLUTE MAXIMUM RATINGS (note 1)

OPL3/4+Codec Portable Clock Source

Electrical Specifications

Parameter Conditions Minimum Typical Maximum Units

Supply Voltage, VDD Referenced to GND 7 V
Inputs Referenced to GND -0.5 VDD+.5V V
Clock Outputs Referenced to GND -0.5 VDD+.5V V
Ambient Operating Temperature 0 70 °C
Soldering Temperature Max of 20 seconds 260 °C
Storage temperature -65 150 °C

DC CHARACTERISTICS

Operating Voltage, VDD 4.5 5.5 V
Input High Voltage, VIH, ICLK VDD/2 + 1 VDD/2 V
Input Low Voltage, VIL, ICLK VDD/2 VDD/2 - 1 V
Input High Voltage, VIH, PD 2 V
Input Low Voltage, VIL, PD 0.8 V
Output High Voltage, VOH IOH=-25mA 2.4 V
Output Low Voltage, VOL IOL=25mA 0.4 V
Output High Voltage, VOH IOH=-4mA VDD-0.4 V
Output Low Voltage, VOL IOL=4mA 0.4 V
Operating Supply Current, IDD No Load 18 mA
Power Down Operating Current, IDDPD No Load 20 µA
Input Capacitance 7 pF
Actual Mean Frequency versus Target Outputs ±0.2 %

AC CHARACTERISTICS

Input Clock Frequency 14.31818 MHz
Input Clock Duty Cycle, 14.318MHz Time above VDD/2 20 80 %
Output Clock Rise Time 0.8 to 2.0V 1.5 ns
Output Clock Fall Time 2.0 to 0.8V 1.5 ns
Output Clock Duty Cycle, 24.576MHz Time above 1.5 V 40 50 60 %
Output Clock Duty Cycle, 16.9344 MHz Time above 1.5 V 45 50 55 %
Output Clock Duty Cycle, 33.868MHz Time above 1.5 V 45 50 55 %
Absolute Clock Period Jitter Pins 4, 5, 6 only -400 200 400 ps
One Sigma Clock Period Jitter Pins 4, 5, 6 only 60 ps

Notes:

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.

2. Typical values are at 25°C.

MDS 1422 B 3 Revision 080698 Printed 11/15/00

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

OPL3/4+Codec Portable Clock Source

Inches

Millimeters

Package Outline and Package Dimensions

8 pin SOIC

E H

Pin 1

h x 45°

D

MK1422

Symbol Min Max Min Max

A 0.055 0.068 1.397 1.7272
b 0.013 0.019 0.330 0.483

D 0.185 0.200 4.699 5.080

E 0.150 0.160 3.810 4.064

H 0.225 0.245 5.715 6.223

e

h 0.015 0.381

Q 0.004 0.01 0.102 0.254

Q

c

e

b

A

Ordering Information

Part/Order Number Marking Package Temperature

MK1422S MK1422S 8 pin SOIC 0 to 70 C

MK1422STR MK1422S Add tape and reel 0 to 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 1422 B 4 Revision 080698 Printed 11/15/00

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