MK1449B Sound/SCSI+Fast Ethernet Clock Description Features The MK1449B is the most cost effective way to generate high quality, high frequency clock outputs for SCSI plus Fast Ethernet devices, or AC97 sound chips. Using Phase-Locked-Loop (PLL) techniques, the device uses a standard fundamental mode, inexpensive 14.31818 MHz crystal or clock to produce two output clocks. • Packaged as 8 pin SOIC • For Fast Ethernet plus SCSI on computer motherboards • For AC97 sound on computer motherboards • Less than 1 ppm synthesis error • Input crystal frequency of 14.31818 MHz • Operating voltages of 3.0 to 5.5V • Available in industrial temperature • Full CMOS level outputs with 25mA drive capability at TTL levels • Ideal for oscillator replacement • Advanced, low power CMOS process The device can accept either a crystal or clock input. Also on the chip is the ability to generate a 1.25x clock of the reference plus the reference, making it possible to generate 20 and 25 MHz clocks from a 20 MHz crystal. Block Diagram VDD GND 2 S1, S0 Output Buffer CLK1 Output Buffer CLK2 PLL Clock Synthesis and Control Circuitry 14.31818MHz crystal X1 or clock Crystal Oscillator X2 1 Revision 120799 Printed 11/15/00 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA•95126• (408)295-9800tel • www.icst.com MDS 1449B C MK1449B Sound/SCSI+Fast Ethernet Clock Pin Assignment Clock Decoding Table (MHz) X1/ICLK 1 8 X2 VDD 2 7 S1 GND 3 6 S0 CLK2 4 5 CLK1 S1 0 0 1 1 S0 0 1 0 1 CLK1 test 40 49.152 x1.25 CLK2 test 25 12.288 Reference 0 = connect directly to ground. 1 = connect directly to VDD. In the 1,1 mode, crystals or clocks from 5 to 27 MHz can be used as an input. Pin Descriptions Number 1 2 3 4 5 6 7 8 Name X1/ICLK VDD GND CLK2 CLK1 S0 S1 X2 Type I P P O O I I O Description Crystal connection or clock input. Connect to a 14.31818MHz parallel resonant crystal. Connect to +3.3V or +5V. Connect to ground. Clock 2 output per Table above. Clock 1 output per Table above. Select 0 for output clocks. Connect to GND or VDD. See table above. Select 1 for output clocks. Connect to GND or VDD. See table above. Crystal connection to a 14.31818 MHz crystal. Leave unconnected for clock input. Key: I = Input, O = output, P = power supply connection 2 Revision 120799 Printed 11/15/00 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA•95126• (408)295-9800tel • www.icst.com MDS 1449B C MK1449B Sound/SCSI+Fast Ethernet Clock Electrical Specifications Parameter Conditions Minimum Typical ABSOLUTE MAXIMUM RATINGS (stresses beyond these can permanently damage the device) Supply Voltage, VDD Referenced to GND Inputs Referenced to GND -0.5 Clock Output Referenced to GND -0.5 Ambient Operating Temperature 0 Industrial temperature -40 Soldering Temperature Max of 10 seconds Storage temperature -65 DC CHARACTERISTICS (VDD = 3.3V unless otherwise noted) Operating Voltage, VDD 3 Input High Voltage, VIH, ICLK only ICLK (Pin 1) (VDD/2)+1 VDD/2 Input Low Voltage, VIL, ICLK only ICLK (Pin 1) VDD/2 Input High Voltage, VIH S0, S1 VDD-0.5 Input Low Voltage, VIL S0, S1 Output High Voltage, VOH IOH=-25mA 2.4 Output Low Voltage, VOL IOL=25mA IDD Operating Supply Current, 5V No Load, 25, 40MHz 18 IDD Operating Supply Current, 3.3V No Load, 25, 40MHz 10 Short Circuit Current CLK output ±70 On-Chip Pull-up Resistor Pin 7 270 Input Capacitance, S1, S0 Pins 6, 7 4 AC CHARACTERISTICS (VDD = 3.3V unless otherwise noted) Input Frequency, crystal input 10 14.31818 Input Frequency, clock input 10 14.31818 Output Frequency VDD = 3.0 to 5.5V 10 Output Clock Rise Time 0.8 to 2.0V 1 Output Clock Fall Time 2.0 to 0.8V 1 Output Clock Duty Cycle at VDD/2 40 49 to 51 Synthesis error, 25, 40 MHz Synthesis error, 12.288, 49.152 MHz Absolute Clock Period Jitter, 20 pF load Deviation from mean ±240 One Sigma Clock Period Jitter, 20 pF load 100 Maximum Units 7 VDD+0.5 VDD+0.5 70 85 260 150 V V V °C °C °C °C 5.5 V V V V V V V mA mA mA kΩ pF (VDD/2)-1 0.5 0.4 27 50 75 60 1 1 MHz MHz MHz ns ns % ppm ppm ps ps 3 Revision 120799 Printed 11/15/00 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA•95126• (408)295-9800tel • www.icst.com MDS 1449B C MK1449B Sound/SCSI+Fast Ethernet Clock External Components / Crystal Selection The MK1449B requires a 0.01µF decoupling capacitor to be connected between VDD and GND. It must be connected close to the MK1449B to minimize lead inductance. No external power supply filtering is required for this device. 33Ω terminating resistors can be used next to the CLK pins. The total on-chip capacitance is approximately 13 pF, so a parallel resonant, fundamental mode crystal should be used. For crystals with a specified load capacitance greater than 13 pF, crystal capacitors should be connected from each of the pins X1 and X2 to ground. The value (in pF) of these crystal caps should be = (CL -13)*2, where CL is the crystal load capacitance in pF. These external capacitors are only required for applications where the exact frequency is critical. For a clock input, connect to X1 and leave X2 unconnected (no capacitors on either). Package Outline and Package Dimensions (For current dimensional specifications, see JEDEC pub. no. 95) 8 pin SOIC E H Pin 1 D A1 A C e B L Inches Symbol Min Max A 0.053 0.069 A1 0.004 0.0098 B 0.013 0.020 C 0.0075 0.0098 D 0.189 0.197 E 0.150 0.157 H 0.228 0.244 e .050 BSC L 0.016 0.05 Millimeters Min Max 1.35 1.75 0.10 0.25 0.33 0.51 0.19 0.25 4.80 5.00 3.80 4.00 5.80 6.20 1.27 BSC 0.41 1.27 Ordering Information Part/Order Number MK1449S MK1449STR MK1449SI MK1449SITR Marking MK1449S MK1449S MK1449SI MK1449SI Package 8 pin SOIC 8 pin SOIC on tape and reel 8 pin SOIC 8 pin SOIC on tape and reel Temperature 0 to 70 °C 0 to 70 °C -40 to 85 °C -40 to 85 °C While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Inc. (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. 4 Revision 120799 Printed 11/15/00 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA•95126• (408)295-9800tel • www.icst.com MDS 1449B C