Datasheet MK2014A, MK2014ATR Datasheet (ICST)

MK2014A

ICRO

C

LOCK

Description

The MK2014A is the ideal way to generate clocks
for Fast Ethernet cards or systems. It provides
20MHz and 25MHz clocks from an inexpensive

14.31818 MHz crystal or clock. In an 8 pin SOIC,
the MK2014A can save component count, board
space, and cost over surface mount crystals and
oscillators, and increase reliability by eliminating
mechanical devices from the board.

The MK2014A is a functionally identical update
of the MK2014 and should be used in all designs.
The only change is in crystal load capacitance as
stated on page 2.

MicroClock offers many other clocks for
computers and computer peripherals. Consult your
MicroClock representative when you need to
remove crystals and oscillators from your board.

Fast Ethernet Clock Source

Features

• Packaged in 8 pin SOIC

• Input crystal or clock frequency of 14.318 MHz

• Lowest jitter in the industry reliably clocks
sensitive Ethernet devices.

• Output clock frequencies of 20.00 MHz and

25.00 MHz

• Zero ppm synthesis error in the output clocks

• Full CMOS outputs with 25mA drive capability
at TTL levels

• 3.3V or 5V±10% supply voltage

• Advanced, low power CMOS process

Block Diagram

14.31818 MHz
crystal or clock

X1

X2

VDD GND

2

Crystal

Oscillator

• Insensitive to input clock duty cycle

Clock Synthesis

and Control

Circuitry

Output

Buffer

Output

Buffer

Output

Buffer

20 MHz

25 MHz

14.318 MHz

MDS 2014A B 1 Revision 121598 Printed 11/15/00

MicroClock Division of ICS • 525 Race Street • San Jose • CA • 95126•[phone]tel•[phone]fax

MK2014A

Pin Assignment

X1/ICLK

VDD
GND

25M

1 8

2
3
4

ICRO

8 pin SOIC

C

LOCK

7
6

5

Suggested Layout

X2
14M

20M

GND

V

0.1µF

G

33Ω (optional)

Fast Ethernet Clock Source

14.3 MHz in

(crystal caps not

shown)

Pin 1

2

3

4

8

7

33Ω (optional)

6

5

33Ω (optional)

14.3MHz
out

20MHz

out

Pin Descriptions

Number Name Type Description

1 X1/ICLK XI Crystal Connection. Connect to a 14.31818 MHz crystal or clock.
2 VDD P Connect to +5V.
3 GND P Connect to ground.
4 25M O 25.000 MHz clock output.
5 GND P Connect to ground.
6 20M O 20.000 MHz clock output.
7 14M O 14.31818 MHz buffered crystal clock output.
8 X2 XO Crystal Connection to a 14.31818 MHz crystal, or leave unconnected for clock input.

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

25MHz out

External Components/Crystal Selection

A minimum number of external components are required for proper oscillation. A decoupling capacitor of

0.1 µF should be connected between VDD and GND on pins 2 and 3, and 33 Ω terminating resistors
should be used on clock outputs with traces longer than 1 inch. For a clock input, connect to X1 and leave
X2 unconnected. For a crystal input, a parallel resonant 14.31818 MHz crystal is recommended. The
frequency accuracy of the crystal should be 30 ppm or better. External capacitors from each of the X1 and
X2 pins to ground should be added with a value in pF equal to (CL-13)*2, where CL is the crystal load

capacitance in pF. So for a crystal with load capacitance of 16 pF, 6 pF capacitors should be used. [Note
that the MK2014S required crystal load capacitors of (CL-4)*2.]

MDS 2014A B 2 Revision 121598 Printed 11/15/00

MicroClock Division of ICS • 525 Race Street • San Jose • CA • 95126•[phone]tel•[phone]fax

MK2014A

ABSOLUTE MAXIMUM RATINGS (note 1)

DC CHARACTERISTICS (at 5.0V unless otherwise noted)

ICRO

C

LOCK

Fast Ethernet 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

Operating Voltage, VDD 4.5 5.5 V
Input High Voltage, VIH, input clock only Clock input 3.5 2.5 V
Input Low Voltage, VIL, input clock only Clock input 2.5 1.5 V
Output High Voltage, VOH IOH=-4mA VDD-0.4 V
Output High Voltage, VOH IOH=-25mA 2.4 V
Output Low Voltage, VOL IOL=25mA 0.4 V
Operating Supply Current, IDD, 5V No Load 19 mA
Operating Supply Current, IDD, 3.3V No Load 10 mA
Input Capacitance 7 pF
Actual Mean Frequency versus Target, note 3 With exact crystal 0 ppm

AC CHARACTERISTICS

Input Clock or Crystal Frequency 14.31818 MHz
Input Crystal Accuracy 30 ppm
Input Clock Duty Cycle, 14.31818MHz Time above 2.5V 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 Time above 1.5V 45 50 55 %
Absolute Clock Period Jitter, 14.318 MHz output -400 250 400 ps
Absolute Clock Period Jitter, 20, 25 MHz outputs -300 150 300 ps
One Sigma Clock Period Jitter All outputs 70 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.

3. Provided an exact clock input or a properly tuned crystal is used as the reference.

MDS 2014A B 3 Revision 121598 Printed 11/15/00

MicroClock Division of ICS • 525 Race Street • San Jose • CA • 95126•[phone]tel•[phone]fax

MK2014A

Inches

Millimeters

ICRO

C

LOCK

Package Outline and Package Dimensions

8 pin SOIC

E H

Pin 1

h x 45°

c

Q

D

e

b

Fast Ethernet Clock Source

Symbol Min Max Min Max

A 0.055 0.070 1.397 1.778
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

A

Ordering Information

While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Incorporated (ICS) 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 ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does
not authorize or warrant any ICS product for use in life support devices or critical medical instruments.

MDS 2014A B 4 Revision 121598 Printed 11/15/00

MicroClock Division of ICS • 525 Race Street • San Jose • CA • 95126•[phone]tel•[phone]fax

Part/Order Number Marking Package Temperature

MK2014A MK2014A 8 pin SOIC 0 to 70 C

MK2014ATR MK2014A Add tape and reel 0 to 70 C