SMSC TMC2005-JT Switch User Manual


 
ARCNET 5 Port HUB Controller
Datasheet
Revision 1.1 (07-24-07) Page 22 SMSC TMC2005-JT
DATASHEET
Method To Connect A Crystal Clock
Connect with external parts as follows:
FIGURE 11 - CONNECTING THE CRYSTAL CLOCK
Note 1: When designing a printed circuit board, keep the patterns as short as possible and don’t cross with other
patterns.
Note 2: When using an external clock like an oscillator module, connect it to XTLI pin and leave XTLO pin open.
When designing a printed circuit board, wire between XTLI pin and oscillator should be short as possible.
nPLLTST pin
nPLLTST must be connect toVDD. The rest of input pins have pull-up resistors built in, but nPLLTST pin does not
have the pull-up resistor. Clock signal cannot ditributed into the TMC2005 if nPLLTST pin is connected GND or is left
open.