PRELIMINARY INFORMATION ICS650-21 System Peripheral Clock Source Description Features The ICS650-21 is a low cost, low jitter, high performance clock synthesizer for system peripheral applications. Using analog/digital Phase-Locked Loop (PLL) techniques, the device accepts a parallel resonant 25 MHz crystal input to produce up to eight output clocks. The device provides clocks for PCI, SCSI, Fast Ethernet, Ethernet, USB, and AC97. The user can select one of three USB frequencies, and also one of two AC97 audio frequencies. The OE pin puts all outputs into a high impedance state for board level testing. All frequencies are generated with less than one ppm error, meeting the demands of SCSI and Ethernet clocking. The ICS650 can be mask customized to produce any frequencies from 1 to 150 MHz. Block Diagram PSEL1:0 Clock Synthesis Circuitry USEL X1/ICLK Crystal Oscillator X2 Output Buffer 2 ASEL 25 MHz crystal or clock • Packaged in 20 pin tiny SSOP (QSOP) • Lower jitter version of ICS650-01 • Operating VDD of 3.3V or 5V • Zero ppm synthesis error in all clocks • Inexpensive 25 MHz crystal or clock input • Provides Ethernet and Fast Ethernet clocks • Provides SCSI clocks • Provides PCI clocks • Selectable AC97 audio clock • Selectable USB clock • OE pin tri-states the outputs for testing • Selectable frequencies on three clocks • Duty cycle of 45/55 for Processor clock and Audio clock • Advanced, low power CMOS process 3 Processor Clocks (Fast Ethernet, SCSI, PCI ) Output Buffer Audio Clock Output Buffers USB Clock Output Buffers 20 MHz Output Buffer 25 MHz Output Enable (all outputs) 1 Revision 010301 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA•95126• (408) 295-9800tel • www.icst.com MDS 650-21 A PRELIMINARY INFORMATION ICS650-21 System Peripheral Clock Source Pin Assignment Processor Clock (MHz) USEL 1 20 PSEL1 X2 2 19 PSEL0 X1/ICLK 3 18 PCLK2 VDD 4 17 PCLK3 VDD 5 16 VDD GND 6 15 ASEL UCLK 7 14 GND 20M 8 13 OFF/14.318M ACLK 9 12 PCLK1 10 11 OE 25M 20 pin (150 mil) SSOP PSEL1 0 0 0 M M M 1 1 1 PSEL0 0 M 1 0 M 1 0 M 1 PCLK1 25.00 37.5 66.66 40.00 33.3334 20.00 20.00 20.00 50 Audio Clock (MHz) ASEL 0 M 1 ACLK 49.152 24.576 14.318 PCLK2,3 50.00 75.00 133.33 80.00 66.6667 40.00 33.3334 66.6667 100 USB Clock (MHz) USEL 0 M 1 UCLK 12 24 48 0 = connect directly to ground, 1 = connect directly to VDD, M=leave unconnected (floating) Pin Descriptions Pin # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Name USEL X2 X1/ICLK VDD VDD GND UCLK 20M ACLK 25M OE PCLK1 OFF/14.318M GND ASEL VDD PCLK3 PCLK2 PSEL0 PSEL1 Type I XO XI P P P O O O O I O O P I P O O I I Description UCLK Select pin. Determines frequency of USB clock per table above. Crystal connection. Connect to parallel mode 25 MHz crystal. Leave open for clock. Crystal connection. Connect to parallel mode 25 MHz crystal, or clock. Connect to VDD. Must be same value as other VDD. Decouple with pin 6. Connect to VDD. Must be same value as other VDD. Connect to ground. USB clock output per table above. Fixed 20 MHz output for Ethernet. AC97 Audio clock output per table above. Fixed 25 MHz reference output for Fast Ethernet. Output Enable. Tri-states all outputs when low. PCLK output number 1 per table above. 14.31818 MHz clock output only when ASEL=VDD. Connect to ground. ACLK Select pin. Determines frequency of Audio clock per table above. Connect to VDD. Must be same value as other VDD. Decouple with pin 14. PCLK output number 3 per table above. PCLK output number 2 per table above. Processor Select pin #0. Determines frequencies on PCLKs 1-3 per table above. Processor Select pin #1. Determines frequencies on PCLKs 1-3 per table above. Key: I = Input; XO/XI = crystal connections; O = output; P = power supply connection 2 Revision 010301 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA•95126• (408) 295-9800tel • www.icst.com MDS 650-21 A PRELIMINARY INFORMATION ICS650-21 System Peripheral 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 mA mA mA pF 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 10 seconds -65 DC CHARACTERISTICS (VDD = 3.3V or 5V unless noted) Operating Voltage, VDD Input High Voltage, VIH Input Low Voltage, VIL Output High Voltage, VOH Output Low Voltage, VOL Output High Voltage, VOH, VDD = 3.3 or 5V Operating Supply Current, IDD, at 5V Operating Supply Current, IDD, at 3.3V Short Circuit Current, VDD = 3.3 Input Capacitance 3.0 2 Select inputs, OE Select inputs, OE VDD=3.3V, IOH=-8mA 2.4 VDD=3.3V, IOL=8mA IOH=-8mA VDD-0.4 No Load, note 2 No Load, note 2 Each output Except X1 0.8 0.4 50 30 ±50 5 AC CHARACTERISTICS (VDD = 3.3V or 5V unless noted) Input Crystal or Clock Frequency Output Clocks Accuracy (synthesis error) Output Clock Rise Time Output Clock Fall Time Output Clock Duty Cycle, UCLCK Output Clock Duty Cycle, PCLCK, ACLCK One Sigma Jitter, except ACLK One Sigma Jitter, ACLK Absolute Clock Period Jitter PCLK, UCLK, 20M Notes: 25.000 All clocks 0.8 to 2.0V 2.0 to 0.8V At VDD/2 At VDD/2 40 45 - 500 50 50 75 120 1 1.5 1.5 60 55 500 MHz ppm ns ns % % ps ps ps 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. With all clocks at highest frequencies. External Components The ICS650 requires a minimum number of external components for proper operation. Decoupling capacitors of 0.1µF should be connected between VDD and GND (on pins 4 and 6, and pins 16 and 14), as close to the chip as possible. A series termination resistor of 33Ω may be used for each clock output. The 25.000 MHz crystal must be connected as close to the chip as possible. The crystal should be a fundamental mode, parallel resonant, 30ppm or better (to meet the Ethernet specs). Crystal capacitors should be connected from pins X1 to ground and X2 to ground. The value of these capacitors is given by the following equation, where CL is the crystal load capacitance: Crystal caps (pF) = (CL -12) x 2. So for a crystal with 16pF load capacitance, two 8pF caps should be used. If a clock input is used, drive it into X1 and leave X2 unconnected. 3 Revision 010301 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA•95126• (408) 295-9800tel • www.icst.com MDS 650-21 A PRELIMINARY INFORMATION ICS650-21 System Peripheral Clock Source Package Outline and Package Dimensions (For current dimensional specifications, see JEDEC Publication No. 95.) 20 pin SSOP E1 INDEX AREA 1 Symbol A A1 b c D e E E1 L E 2 Inches Min Max 0.053 0.069 0.004 0.010 0.008 0.012 0.007 0.010 0.337 0.344 .025 BSC 0.228 0.244 0.150 0.157 0.016 0.050 Millimeters Min Max 1.35 1.75 0.10 0.25 0.20 0.30 0.18 0.25 8.55 8.75 0.635 BSC 5.80 6.20 3.80 4.00 0.40 1.27 D A1 A c e b L Ordering Information Part/Order Number ICS650R-21 ICS650R-21T ICS650R-21I ICS650R-21IT Marking ICS650R-21 ICS650R-21 ICS650R-21I ICS650R-21I Package 20 pin SSOP 20 pin SSOP 20 pin SSOP 20 pin SSOP Shipping Tubes Tape and Reel Tubes 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, 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. 4 Revision 010301 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA•95126• (408) 295-9800tel • www.icst.com MDS 650-21 A