MK74CB214 Dual 1 to 7 Buffalo™ Clock Driver Description Features The MK74CB214 Buffalo™ is a monolithic CMOS high speed clock driver which is ideal for Pentium™, 486, and RISC processor systems. It consists of two identical single input to seven lowskew output, non-inverting clock drivers. When combined with MicroClock’s MK14xx series of low jitter clock synthesizers, the two chips form an unequaled high performance clocking scheme for new processors. This is the only solution on the market that meets Intel’s specs for skew and jitter. Many new Pentium systems require up to seven outputs each of two low-skew clocks. This monolithic solution eliminates any concern for part-to-part skew matching. The MK74CB214 is packaged in the tiny 20 pin SSOP, which uses the same board space as the narrow 14 pin SOIC. An added feature of the chip is the ability to produce both 3.3V and 5V amplitude clocks by connecting different voltages to VDDA and VDDB. See MAN03 for dual voltage operation. • Tiny 20 pin SSOP (150 mil) package • Dual one input to seven output clock drivers • Outputs are skew matched to within 250ps • A outputs and B outputs matched to 500ps • 3.3V±10% and/or 5V±10% supply voltage • Each set of seven clock drivers can run from different supply voltages, making it possible to have 3.3V and 5V amplitude clock outputs from the same chip • Clock speeds up to 66.67 MHz Family of MicroClock Parts The MK74CB214 Buffalo™ is designed to be used with MicroClock’s clock synthesizer devices, which will produce the CPU, memory, and local bus clocks. The inputs of the Buffalo are matched to the outputs of MicroClock clock synthesizers. Consult MicroClock for applications support. Block Diagram VDDA VDDB INA INB QA0 QB0 QA1 QB1 QA2 QB2 QA3 QB3 QA4 QB4 QA5 QB5 QA6 QB6 GNDA GNDB 1 Revision 051396 Printed 11/16/00 MicroClock Incorporated•1171 North Fourth St.•San Jose•CA•95112•(408)295-9800tel•(408)295-9818fax MDS 74CB214 B MK74CB214 Dual 1 to 7 Buffalo™ Clock Driver Pin Assignment INA QA0 QA1 VDDA QA2 QA3 GNDA QA4 QA5 QA6 1 2 3 4 5 6 7 8 9 10 Suggested Layout 20 19 18 17 16 15 14 13 12 11 INB QB0 QB1 VDDB QB2 QB3 GNDB QB4 QB5 QB6 V V 0.1µF 0.1µF G G For simplicity, terminating resistors (if needed) are not shown for the outputs, but should be placed as close to the device as possible. It is most critical to have the 0.1µF decoupling capacitors closest. V = connect to VDD G = connect to GND Pin Descriptions Number Name 1 INA 2, 3 QA0, QA1 4 VDDA 5, 6 QA2, QA3 7 GNDA 8, 9, 10 QA4, QA5, QA6 11, 12, 13 QB6, QB5, QB4 14 GNDB 15, 16 QB3, QB2 17 VDDB 18, 19 QB1, QB0 20 INB Type I O P O P O O P O P O I Description Clock input for seven A outputs. Clock A outputs. Power supply for seven A buffers. Connect to +3.3V or +5V. Clock amplitude will match. Clock A outputs. Connect to ground. Clock A outputs. Clock B outputs. Connect to ground. Clock B outputs. Power supply for seven B buffers. Connect to +3.3V or +5V. Clock amplitude will match. Clock B outputs. Clock input for sevent B outputs. Type: I = Input, O = output, P = power supply connection 2 Revision 051396 Printed 11/16/00 MicroClock Incorporated•1171 North Fourth St.•San Jose•CA•95112•(408)295-9800tel•(408)295-9818fax MDS 74CB214 B MK74CB214 Dual 1 to 7 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 mA 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 10 seconds -65 DC CHARACTERISTICS (VDD = 5V unless noted) Operating Voltage, VDD Input High Voltage, VIH (INA, INB pins) Input Low Voltage, VIL (INA, INB pins) Output High Voltage, 3.3V and 5V Output High Voltage, 3.3V and 5V Output Low Voltage, 3.3V and 5V Operating Supply Current, IDD, at 66.6MHz Short Circuit Current Short Circuit Current at 3.3V Input Capacitance 3.0 VDD-1 IOH=-8mA IOH=-12mA IOL=12mA No Load Each output Each output VDD/2 VDD/2 1 VDD-0.4 2.4 0.8 20 ±70 ±35 7 AC CHARACTERISTICS (VDD = 5V unless noted) Input Clock Frequency Propagation Delay with load=10pF Propagation Delay with load=10pF Output Clock Rise Time, 3.3V and 5V Output Clock Fall Time, 3.3V and 5V Output Clock Rising Edge Skew, 3.3V and 5V Output Clock A to B Skew, 3.3V and 5V Maximum load per output pin Maximum load per side of 7 outputs At VDD=3.3V 0.8 to 2.0V 2.0 to 0.8V At VDD/2. Note 2 At VDD/2. Note 3 At 66.66 MHz Note 4 2 2.5 3.5 4.5 50 100 67 5 6.5 1.5 1.5 250 500 25 105 MHz ns ns ns ns ps ps pF pF 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. Between any two A outputs, or any two B outputs, with equal loading. 3. Between any clock A output and any clock B output with INA connected to INB. With VDDA=VDDB and equal loading. Combined with the 250ps uncertainty of MicroClock’s Clock Synthesizers, this adds to a 750ps total. -3 4. This is the load sum of all A outputs, or all B outputs, at 66.66MHz. The formula for per side load is CL (F) = 7 x 10 f (in Hz) 3 Revision 051396 Printed 11/16/00 MicroClock Incorporated•1171 North Fourth St.•San Jose•CA•95112•(408)295-9800tel•(408)295-9818fax MDS 74CB214 B MK74CB214 Dual 1 to 7 Buffalo™ Clock Driver Package Outline and Package Dimensions E e Symbol A b c D E H e h Q H h x 45° D Q 20 pin SSOP b Inches Min Max 0.061 0.068 0.008 0.012 0.007 0.010 0.337 0.344 0.150 0.160 0.230 0.245 .025 BSC 0.016 0.005 0.01 Millimeters Min Max 1.55 1.73 0.203 0.305 0.191 0.254 8.560 8.740 3.810 4.064 5.842 6.223 0.64 BSC 0.406 0.127 0.254 A c Ordering Information Part/Order Number Marking Package Temperature MK74CB214R MK74CB214RTR 74CB214R 74CB214R 20 pin SSOP Add Tape & Reel 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. Buffalo is a trademark of MicroClock Incorporated Pentium is a trademark of Intel Corporation 4 Revision 051396 Printed 11/16/00 MicroClock Incorporated•1171 North Fourth St.•San Jose•CA•95112•(408)295-9800tel•(408)295-9818fax MDS 74CB214 B