COM90C66 Datasheet, PDF (7/76 Pages) SMSC Corporation – ARCNET Controller/Transceiver with AT Interface and On-Chip RAM

PLCC
PIN NO.
NAME
33, 34 Crystal
Oscillator
59 CA Clock
58 Clock
1, 43
21, 68
60-61
Power Supply
Ground
No Connect
DESCRIPTION OF PIN FUNCTIONS
SYMBOL
XTAL1,
XTAL2
CACLK
CLK
Vcc
GND
NC
DESCRIPTION
An external parallel resonant 20 MHz crystal should be
connected to these pins. If an external 20 MHz TTL clock
is used instead, it must be connected to XTAL1 with a
390Ω pull-up resistor and XTAL2 should be left floating.
Output. This is the start/stop CA clock and should be left
floating for typical operation.
Output. This is a general purpose 5 MHz clock and
should be left floating for typical operation.
+5 Volt Power Supply pin.
Ground pins.
Make no connection to these pins.
7