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 PentiumTM 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 * PentiumTM 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) MDS 1442/3 F 1 Revision 101001 Integrated Circuit Systems, Inc. * 525 Race Street * San Jose * CA * 95126 *(408)297-1201tel * www.icst.com MK1442/MK1443 SCSI and Ethernet Clock Source Pin Assignment CPUS1 1 CPU Clock Decoding 16 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 (MK1442) (MK1443) 20M 8 CPUS1 CPUS0 CPUS0 9 KBOUT 16 pin (150 mil) SOIC Pin Descriptions 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 Number Name Type 1 CPUS1 TI Description Select 1 for 2XCPU and CPU frequencies. See Table above, note 5 below. 2 X2 O Crystal connection. Connect to 14.318 MHz crystal, or leave unconnected for clock input. 3 X1 I Crystal connection. Connect to 14.318 MHz crystal, or drive with a 14.318MHz clock. 4 VDD P Connect to +5V or 3.3V. Must be same voltage as pin 13. 5 GND P Connect to ground. 6 24M O 24.00 MHz floppy (or super I/O) clock output. 7 40M O 40.00 MHz clock output 8 20M O 20.000 MHz Ethernet clock output 9 KBOUT O Keyboard clock. 12.00 MHz on -01, 8.00 MHz on -02, 16.00 MHz on -03 version. 10 OE I Output Enable on 1442. Tri-states all clock outputs when this input is low. Internal pull-up. 11 14.3M O 14.318 MHz system clock output. 12 GND P Connect to ground. 13 VDD P Connect to +5V or 3.3V. Must be same voltage as pin 4. 14 CPU O CPU output. See Table above. Rising edge is within 250ps of 2XCPU. 15 2XCPU O 2XCPU output. See Table above. Rising edge is within 250ps of CPU. 16 CPUS0 TI 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. MDS 1442/3 F 2 Revision 101001 Integrated Circuit Systems, Inc. * 525 Race Street * San Jose * CA * 95126 *(408)297-1201tel * www.icst.com MK1442/MK1443 SCSI and Ethernet Clock Source Electrical Specifications Parameter Conditions Minimum Typical Maximum Units ABSOLUTE MAXIMUM RATINGS (note 1) Supply voltage, VDD Referenced to GND Inputs and Clock Outputs Referenced to GND Ambient Operating Temperature Soldering Temperature -0.5 0 V V 70 C 260 C -65 150 C 3.0 5.5 V Max of 20 seconds Storage Temperature 7 VDD+0.5 DC CHARACTERISTICS (VDD = 5V unless noted) Operating Voltage, VDD Input High Voltage, VIH OE (pin 10) 2.0 Input Low Voltage, VIL OE (pin 10) Input High Voltage, VIH CPUS0,1 (pins 1,16) Input Mid-level Voltage CPUS0,1 (pins 1,16) Input Low Voltage, VIL CPUS0,1 (pins 1,16) 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 Input High Voltage, VIH VDD=3.3V, OE pin Input Low Voltage, VIL VDD=3.3V, OE pin Output High Voltage, VOH VDD=3.3V, IOH=-8mA Output Low Voltage, VOL VDD=3.3V, IOL=8mA Operating Supply Current, IDD No Load, 80 MHz Short Circuit Current Each output 0.8 VDD-0.5 0.5 0.4 1.9 0.4 V V V V 0.4 V 35 mA 100 mA 250 k 7 0-70C, note 2 V V 2.4 Input Capacitance V V Leave pin unconnected or tri-stated On-Chip Pull-up Resistor Frequency Accuracy of 20.000 MHz clock V -1 pF 1 ppm 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 Output Clock Duty Cycle At 1.5V Cycle to Cycle Jitter 50-80 MHz clocks Skew of 2XCPU with respect to CPU Rising edges at 1.5V 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 s 47.5 49 to 51 52.5 % 45 49 to 51 55 % 250 ps -250 0 250 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. Provided proper crystal and capacitor components are used - consult ICS. MDS 1442/3 F 3 Revision 101001 Integrated Circuit Systems, Inc. * 525 Race Street * San Jose * CA * 95126 *(408)297-1201tel * www.icst.com MK1442/MK1443 SCSI and Ethernet Clock Source Package Outline and Package Dimensions E 16 pin SOIC narrow Inches Symbol Min Max A 0.055 0.070 b 0.013 0.019 c 0.007 0.010 D 0.385 0.400 E 0.150 0.160 H 0.225 0.245 e .050 BSC h 0.016 Q 0.004 0.01 H h x 45 D A c Q e 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 b Ordering Information Part/Order Number Marking Keyboard frequency Package Temperature MK1442-02S MK1442-02S 8 MHz 16 pin SOIC 0-70C MK1442-03S MK1442-03S 16 MHz 16 pin SOIC 0-70C MK1443-01S MK1443-01S 12 MHz 16 pin SOIC 0-70C MK1443-02S MK1443-02S 8 MHz 16 pin SOIC 0-70C MK144x-0xSTR MK144x-0xS x Add Tape & Reel 0-70C While the information presented herein has been checked for both accuracy and reliability, 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. PentiumTM is a registered trademark of Intel Corporation MDS 1442/3 F 4 Revision 101001 Integrated Circuit Systems, Inc. * 525 Race Street * San Jose * CA * 95126 *(408)297-1201tel * www.icst.com