MK2011 ICST | Alldatasheet

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Technical content

Fast Ethernet Clock Source MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax ICR OCLOC K The MK2011 is the ideal way to generate clocks for Fast Ethernet cards or systems. It provides 20MHz, 25MHz, and 50MHz clocks. In an 8 pin SOIC, the MK2011 can save component count, board space, and cost over surface mount crystals and oscillators, and increase reliability by eliminating two or three mechanical devices from the board. MicroClock offers many other clocks for computers and computer peripherals. Consult MicroClock when you need to remove crystals and oscillators from your board. Block Diagram Description Features

  • Packaged in 8 pin SOIC
  • Input crystal or clock frequency of 20.00 MHz
  • Lowest jitter in the industry reliably clocks sensitive Ethernet devices.
  • Output clock frequencies of 20.00 MHz, 25.00 MHz, and 50.00 MHz
  • 25mA drive capability at TTL levels
  • 3.3V or 5V±10% supply voltage
  • Advanced, low power CMOS process
  • Insensitive to input clock duty cycle Crystal Oscillator VDD GND PLL Clock Synthesis Circuitry Output Buffer Output Buffer

50 MHz

20 MHz

20.00 MHz

Fast Ethernet Clock Source MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax ICR OCLOC K Number Name Type Description 1 X1/ICLK I Crystal Connection. Connect to a 20.000 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 50M O 50.000 MHz clock output. 6 GND P Connect to ground. 7 20M O 20.000 MHz buffered crystal clock output. 8 X2 O Crystal Connection to a 20.000 MHz crystal, or leave unconnected for clock input. Pin Descriptions Key: I = Input, O = output, P = power supply connection Pin Assignment 20.00 MHz in (crystal caps not shown) Pin 1 33Ω (optional) 0.1µF 25MHz out 50MHz out G V 33Ω (optional) Suggested Layout 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 20.000 MHz, 16pF load, crystal is recommended. The frequency tolerance of the crystal should be 50ppm or better. For a clock input, connect to X1 and leave X2 unconnected. A decoupling capacitor of 0.1µF 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. 33Ω (optional) 20MHz out1 8 X1/ICLK 20M GND VDD GND 50M 8 pin SOIC 25M

Fast Ethernet Clock Source MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax ICR OCLOC K 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. Electrical Specifications Parameter Conditions Minimum Typical Maximum Units ABSOLUTE MAXIMUM RATINGS (note 1) ABSOLUTE MAXIMUM RATINGS (note 1) 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 (at 5.0V unless otherwise noted)DC CHARACTERISTICS (at 5.0V unless otherwise noted)DC CHARACTERISTICS (at 5.0V unless otherwise noted) 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 With exact crystal 0 ppm AC CHARACTERISTICS Input Clock or Crystal Frequency 20.0000 MHz Input Crystal Accuracy 50 ppm Input Clock Duty Cycle, 20.000MHz 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, 20 MHz output -400 250 400 ps Absolute Clock Period Jitter, 50, 25 MHz clocks -300 150 300 ps One Sigma Clock Period Jitter All outputs 70 ps

Fast Ethernet Clock Source MicroClock Division of ICS•1271 Parkmoor Ave.•San Jose•CA•95126•(408)295-9800tel•(408)295-9818fax ICR OCLOC K 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. Package Outline and Package Dimensions Inches Inches Millimeters Millimeters 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 .050 BSC .050 BSC 1.27 BSC 1.27 BSC h 0.015 0.381 Q 0.004 0.01 0.102 0.254 8 pin SOIC

Ordering Information

Part/Order Number Marking Package Temperature MK2011S MK2011S 8 pin SOIC 0-70°C MK2011STR MK2011S Add tape and reel 0-70°C c A b D E H e h x 45° Q Pin 1