MK74CB115

1 to 16 Buffalo™ Clock Driver

MDS 74CB115 D

4

Revision 020800

Printed 11/16/00

Integrated Circuit Systems, Inc. • 525 Race St. • San Jose • CA • 95126 • (408) 295-9800tel • www.icst.com

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

200

150

100

50

0

80

60

40

20

0

Do not operate in this area .

Load Capacitance/per pin (pF), all 16 outputs loaded

Graph 1

MK74CB115

Maximum Speed at 3.3 V