MK1442/MK1443 SCSI and Ethernet Clock Source Description Features The MK1442/3 are the ideal way to generate clocks for desktop computer motherboards and LAN workstations. Using analog Phase-Locked Loop (PLL) techniques, the devices accept a 14.318 MHz crystal input to produce multiple output clocks up to 100 MHz. They provide 2XCPU, CPU, floppy controller, keyboard, system, SCSI and Ethernet clocks. The MK1442/3 are perfect for new Pentium™ Processor, PCI bus and 486 systems. The devices can operate at 5V or 3.3V up to and including 80MHz on the CPU clock. • Provides exact frequency Ethernet and SCSI clocks • 5V or 3.3V (up to 80MHz) operation • Output clock frequencies up to 100 MHz • Pentium™ Processor compatible timing • 486 compatible smooth frequency transitions • Seven or eight output clocks • Compatible with X86 and 680X0 CPUs • Skew controlled 2X and 1X CPU to within 250ps • Packaged in 16 pin skinny SOIC or PDIP • Duty cycle of 47.5/52.5 up to 66.66 MHz • Duty cycle of 45/55 up to 100 MHz • Total of 15 different selectable CPU frequencies • Tri-state outputs for board level testing • 25mA drive capability at TTL levels • Keyboard frequencies of 12MHz (-01), 8MHz (-02), or 16MHz (-03) • Advanced, low power CMOS process • MK1442 - output enable • MK1443 - two 14.318 MHz outputs The devices are identical except the MK1442 has an Output Enable (OE) pin that tri-states all outputs when taken low, and the MK1443 has an extra 14.318 MHz clock. Block Diagram VDD GND CPUS0 CPUS1 ÷2 Clock Synthesis and Control Circuitry 14.318 MHz crystal X1 Crystal Oscillator X2 Output Buffer 2XCPU Output Buffer CPU Output Buffer 8.00, 12.00, or 16.00 MHz Output Buffer 24.00 MHz Output Buffer 40.000 MHz Output Buffer 20.000 MHz Output Buffer 14.318 MHz (MK1443 only) Output Buffer 14.318 MHz OE (all outputs, MK1442 only) 1 Revision 111500 Printed 11/15/00 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose • CA • 95126 •(408)297-1201tel • www.icst.com MDS 1442/3 E MK1442/MK1443 SCSI and Ethernet Clock Source CPU Clock Decoding Pin Assignment CPUS1 1 16 CPUS0 X2 2 15 2XCPU X1 3 14 CPU VDD 4 13 VDD GND 5 12 GND 24M 6 11 14.3M 40M 7 10 OE or 14.3M 20M 8 9 (MK1442) Pin Descriptions Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Name CPUS1 X2 X1 VDD GND 24M 40M 20M KBOUT OE 14.3M GND VDD CPU 2XCPU CPUS0 Type TI O I P P O O O O I O P P O O TI (MK1443) KBOUT CPUS1 CPUS0 2XCPU (MHz) CPU (MHz) 0 0 8.00 4.00 0 M 80.00 40.00 0 1 33.33 16.67 M 0 100.00 (note 4) 50.00 (note 4) M M 66.67 33.33 M 1 60.00 30.00 1 0 50.00 25.00 1 M 20.00 10.00 1 1 25.00 12.50 Notes: 1. M = mid point (input is left floating. See note 5 below) 2. Actual frequencies are within 0.05% of those shown. 3. Transitions between mean frequencies are smooth, and do not violate Intel’s 0.1% per cycle specification. 4. These selections are not guaranteed to operate at 3V Description Select 1 for 2XCPU and CPU frequencies. See Table above, note 5 below. Crystal connection. Connect to 14.318 MHz crystal, or leave unconnected for clock input. Crystal connection. Connect to 14.318 MHz crystal, or drive with a 14.318MHz clock. Connect to +5V or 3.3V. Must be same voltage as pin 13. Connect to ground. 24.00 MHz floppy (or super I/O) clock output. 40.00 MHz clock output 20.000 MHz Ethernet clock output Keyboard clock. 12.00 MHz on -01, 8.00 MHz on -02, 16.00 MHz on -03 version. Output Enable on 1442. Tri-states all clock outputs when this input is low. Internal pull-up. 14.318 MHz system clock output. Connect to ground. Connect to +5V or 3.3V. Must be same voltage as pin 4. CPU output. See Table above. Rising edge is within 250ps of 2XCPU. 2XCPU output. See Table above. Rising edge is within 250ps of CPU. Select 0 for 2XCPU and CPU frequencies. See Table above, note 5 below. Key: I = Input, TI = three level input, O = output, P = power supply connection Note 5: The TI inputs are internally held at mid-level, so they cannot drift high or low. Crystal and Capacitor Selection for Ethernet Accuracy The MK1442/3 requires external crystals between the X1 and X2 pins and ground, as shown on the block diagram on page 1. For an accurate Ethernet frequency of 20.000 MHz, a 14.31818 MHz ±50 ppm, parallel resonant crystal with a load capacitance of 16pF is recommended, along with 22 pF ±5% (NPO dielectric) chip capacitors. If the 20 MHz output is not used for Ethernet, any 22 pF capacitors will work. 2 Revision 111500 Printed 11/15/00 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose • CA • 95126 •(408)297-1201tel • www.icst.com MDS 1442/3 E MK1442/MK1443 SCSI and Ethernet Clock Source Electrical Specifications Parameter Conditions Minimum Typical Maximum Units 7 VDD+0.5 70 260 150 V V °C °C °C 5.5 V V V V V V V V V V V V V mA mA kΩ pF ppm ABSOLUTE MAXIMUM RATINGS (note 1) Supply voltage, VDD Inputs and Clock Outputs Ambient Operating Temperature Soldering Temperature Storage Temperature Referenced to GND Referenced to GND -0.5 0 Max of 20 seconds -65 DC CHARACTERISTICS (VDD = 5V unless noted) Operating Voltage, VDD Input High Voltage, VIH Input Low Voltage, VIL Input High Voltage, VIH Input Mid-level Voltage Input Low Voltage, VIL Output High Voltage, VOH Output High Voltage, VOH Output Low Voltage, VOL Input High Voltage, VIH Input Low Voltage, VIL Output High Voltage, VOH Output Low Voltage, VOL Operating Supply Current, IDD Short Circuit Current On-Chip Pull-up Resistor Input Capacitance Frequency Accuracy of 20.000 MHz clock 3.0 2.0 OE (pin 10) OE (pin 10) 0.8 CPUS0,1 (pins 1,16) VDD-0.5 CPUS0,1 (pins 1,16) Leave pin unconnected or tri-stated CPUS0,1 (pins 1,16) 0.5 IOH=-4mA VDD-0.4 IOH=-25mA 2.4 IOL=25mA 0.4 VDD=3.3V, OE pin 1.9 VDD=3.3V, OE pin 0.4 VDD=3.3V, IOH=-8mA 2.4 VDD=3.3V, IOL=8mA 0.4 No Load, 80 MHz 35 Each output ±100 250 7 0-70°C, note 2 -1 1 AC CHARACTERISTICS (VDD = 5V unless noted) Input Frequency 14.31818 MHz 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, CPU and 2XCPU 1.5V, up to 67MHz 47.5 49 to 51 52.5 % Output Clock Duty Cycle At 1.5V 45 49 to 51 55 % Cycle to Cycle Jitter 50-80 MHz clocks 250 ps Skew of 2XCPU with respect to CPU Rising edges at 1.5V -250 0 250 ps Transition time, 8MHz to 100MHz VDD=3.3 or 5V 4 ms Transition time, 100MHz to 8MHz VDD=3.3 or 5V 2.5 ms Output Enable Time, OE high to output on VDD=3.3 or 5V 50 ns Output Disable Time, OE low to tri-state VDD=3.3 or 5V 3 µs 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. Provided proper crystal and capacitor components are used - consult MicroClock. 3 Revision 111500 Printed 11/15/00 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose • CA • 95126 •(408)297-1201tel • www.icst.com MDS 1442/3 E MK1442/MK1443 SCSI and Ethernet Clock Source Package Outline and Package Dimensions E e Symbol A b c D E H e h Q H h x 45° D Q 16 pin SOIC narrow b Inches Min Max 0.055 0.070 0.013 0.019 0.007 0.010 0.385 0.400 0.150 0.160 0.225 0.245 .050 BSC 0.016 0.004 0.01 Millimeters Min Max 1.397 1.778 0.330 0.483 0.191 0.254 9.779 10.160 3.810 4.064 5.715 6.223 1.27 BSC 0.406 0.102 0.254 A c Ordering Information Part/Order Number Marking Keyboard frequency Package Temperature MK1442-01S MK1442-02S MK1442-03S MK1443-01S MK1443-02S MK1443-03S MK144x-0xSTR MK1442-01S MK1442-02S MK1442-03S MK1443-01S MK1443-02S MK1443-03S MK144x-0xS 12 MHz 8 MHz 16 MHz 12 MHz 8 MHz 16 MHz x 16 pin SOIC 16 pin SOIC 16 pin SOIC 16 pin SOIC 16 pin SOIC 16 pin SOIC Add Tape & Reel 0-70°C 0-70°C 0-70°C 0-70°C 0-70°C 0-70°C 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. Pentium™ is a registered trademark of Intel Corporation 4 Revision 111500 Printed 11/15/00 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose • CA • 95126 •(408)297-1201tel • www.icst.com MDS 1442/3 E