PRELIMINARY INFORMATION MK74CB44 Quad 1 to 4 Buffalo™ Clock Driver Description Features The MK74CB44 Buffalo™ is a monolithic CMOS high speed clock driver. It consists of four identical single input to four low-skew output, non-inverting clock drivers. When combined with ICS’s MK series of low jitter clock synthesizers, the chips form an unequaled high performance clocking scheme. This monolithic solution can eliminate concern for part-to-part skew matching. The MK74CB44 is packaged in the tiny 28 pin SSOP, which uses the same board space as the narrow 16 pin SOIC. • Tiny 28 pin SSOP (150 mil) package • Quad one input to four output clock drivers • Outputs are skew matched to within 250ps • A, B, C and D banks matched to 250ps • 3.3V±10% and/or 5V±10% supply voltage • Clock speeds up to 200 MHz • For tighter skew matching, more outputs, or other speeds, consult ICS for other solutions Family of ICS Parts The MK74CB44 Buffalo™ is designed to be used with ICS’s clock synthesizer devices. The inputs of the Buffalo are matched to the outputs of ICS clock synthesizers. Consult ICS for applications support. Block Diagram VDD 4 INA QA0 IND QD0 QA1 QD1 QA2 QD2 QA3 QD3 QB0 QC0 QB1 QC1 QB2 QC2 QB3 QC3 INB INC 4 GND 1 Revision 022000 Printed 11/17/00 Integrated Circuit Systems, Inc. • 525 Race St. • San Jose • CA • 95126 • (408)295-9800tel • www.icst.com MDS 74CB44 B PRELIMINARY INFORMATION MK74CB44 Quad 1 to 4 Buffalo™ Clock Driver Pin Assignment INA QA0 QA1 QA2 VDD VDD QA3 QB0 GND GND QB1 QB2 QB3 INB 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Suggested Layout 28 27 26 25 24 23 22 21 20 19 18 17 16 15 IND QD0 QD1 QD2 VDD VDD QD3 QC0 GND GND QC1 QC2 QC3 INC V V 0.01µF 0.01µF G G For simplicity,series terminating resistors (required) are not shown for the outputs, but should be placed as close to the device as possible. It is most critical to have the 0.01µF decoupling capacitors closest. V = connect to VDD G = connect to GND Pin Descriptions Number 1 2, 3, 4 5, 6 7 8 9, 10 11, 12, 13 14 15 16, 17, 18 19, 20 21 22 23, 24 25, 26, 27 28 Name Type INA I QA0, QA1, QA2 O VDD P QA3 O QB0 o GND P QB1, QB2, QB3 O INB I INC I QC3, QC2, QC1 O GND P QC0 O QD3 O VDD P QD2, QD1, QD0 O IND I Description Clock input for four A outputs. Clock A outputs. Power supply. Connect to +3.3 V or +5 V. Must be the same as pins 23, 24. Clock A output. Clock B output. Connect to ground. Clock B outputs. Clock input for four B outputs. Clock input for four C outputs. Clock C outputs. Connect to ground. Clock C output. Clock D output. Power supply. Connect to +3.3 V or +5 V. Must be the same as pins 5, 6. Clock D outputs. Clock input for four D outputs. Type: I = Input, O = output, P = power supply connection 2 Revision 022000 Printed 11/17/00 Integrated Circuit Systems, Inc. • 525 Race St. • San Jose • CA • 95126 • (408)295-9800tel • www.icst.com MDS 74CB44 B PRELIMINARY INFORMATION MK74CB44 Quad 1 to 4 Buffalo™ Clock Driver Electrical Specifications Parameter Conditions Minimum Typical Maximum Units 7 VDD+0.5 VDD+0.5 70 260 150 V V V °C °C °C 5.5 V V V V V V mA Ω mA pF ABSOLUTE MAXIMUM RATINGS (Note 1) Supply Voltage, VDD Inputs Clock Outputs Ambient Operating Temperature Soldering Temperature Storage Temperature Referenced to GND Referenced to GND Referenced to GND 0.5 0.5 0 Max of 20 seconds -65 DC CHARACTERISTICS (VDD = 3.3 V unless noted) Operating Voltage, VDD Input High Voltage, VIH Input Low Voltage, VIL Output High Voltage Output High Voltage Output Low Voltage Operating Supply Current, IDD, at 100 MHz Output Impedance Short Circuit Current Input Capacitance 3.0 VDD-1 IOH=-8mA IOH=-12mA IOL=12mA No Load 3.3 VDD/2 VDD/2 1 VDD-0.4 2.4 0.8 55 14 50 7 Each output AC CHARACTERISTICS (VDD = 3.3 V unless noted) Input Clock Frequency Propagation Delay with load=15pF Output Clock Rise Time Output Clock Fall Time Output Clock Rising Edge Skew Output Clock Bank to Bank Skew Note 4, 5 0 1.4 0.8 to 2.0V 2.0 to 0.8V At VDD/2. Note 2 At VDD/2. Note 3 100 100 200 3 2 2 250 250 MHz ns ns ns ps 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. Within any bank of four outputs, with equal loading. 3. Between any two banks of four with their inputs connected together, and equal loading. 4. At VDD = 3.3 V, 70°C, series termination of 33 Ω per pin, 8 pF load per pin. 5. See discussion and graph of speed versus load. 3 Revision 022000 Printed 11/17/00 Integrated Circuit Systems, Inc. • 525 Race St. • San Jose • CA • 95126 • (408)295-9800tel • www.icst.com MDS 74CB44 B PRELIMINARY INFORMATION MK74CB44 Quad 1 to 4 Buffalo™ Clock Driver Maximum Speed/Application Notes The maximum speed at which the chip can operate is limited by power dissipation of the package. Graph 1 shows the operating frequency plotted against load capacitance per pin for a die temperature of 125°C. This is at VDD = 3.3 V, 70°C and with 33 Ω series termination resistor. The termination resistors are essential because they allow a large proportion of the total power to be dissipated outside the package. Reducing or eliminating the series termination will cause an increase in die temperature. It is not recommended to operate the chip at die temperature greater than 125°C. Also note that the load capacitance per pin must include PC board parasitics such as trace capacitance. ICS has other buffers specified to 250 MHz with heavier loads. If not all outputs of the chip are used, it is possible to operate the chip faster with larger loads. Unused outputs should be left unconnected. Consult ICS for your specific requirement. 300 250 Do not operate in this area . 200 150 100 50 0 0 20 40 60 80 Load Capacitance/per pin (pF), all 16 outputs loaded Graph 1 MK74CB44 Maximum Speed at 3.3 V 4 Revision 022000 Printed 11/17/00 Integrated Circuit Systems, Inc. • 525 Race St. • San Jose • CA • 95126 • (408)295-9800tel • www.icst.com MDS 74CB44 B PRELIMINARY INFORMATION MK74CB44 Quad 1 to 4 Buffalo™ Clock Driver Package Outline and Package Dimensions (For current dimensional specifications, see JEDEC Publication No. 95.) 28 pin SSOP E1 Symbol A A1 b c D e E E1 L E D A1 Millimeters Min Max 1.35 1.75 0.102 0.254 0.203 0.305 0.191 0.254 9.804 10.008 0.635 BSC 5.791 6.198 3.810 3.988 0.406 1.270 A c e Inches Min Max 0.053 0.069 0.004 0.010 0.008 0.012 0.007 0.010 0.386 0.394 .025 BSC 0.228 0.244 0.150 0.157 0.016 0.050 b L Ordering Information Part/Order Number Marking Package Temperature MK74CB44R MK74CB44RTR MK74CB44R MK74CB44R 28 pin SSOP Add Tape & Reel 0-70°C 0-70°C While the information presented herein has been checked for both accuracy and reliability, ICS 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 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. Buffalo is a trademark of ICS Incorporated 5 Revision 022000 Printed 11/17/00 Integrated Circuit Systems, Inc. • 525 Race St. • San Jose • CA • 95126 • (408)295-9800tel • www.icst.com MDS 74CB44 B