COM20019I-HT Standard Microsystems (SMSC), COM20019I-HT Datasheet - Page 10

• Manufacturer Part Number: COM20019I-HT
• Manufacturer: Standard Microsystems (SMSC)

Specifications of COM20019I-HT

• Number Of Transceivers: 1
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (min): 4.5V
• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Compliant

Rev. 11-07-08
PLCC
15, 28
7, 14,
18
19
20
21
16
17
22
13
PIN NO
18, 23,
19, 27,
33, 35,
38, 40,
42, 47,
32, 43
30, 41
14-17,
TQFP
6, 11,
8, 20,
3, 5,
24
25
28
29
21
22
48
nPulse 1
nPulse 2
Receive In
nTransmit
Enable
Crystal
Oscillator
Power
Supply
Ground
N/C
NAME
nPULSE1
XTAL1
nPULSE2
SYMBOL
nTXEN
XTAL2
RXIN
VDD
VSS
N/C
DATASHEET
TRANSMISSION MEDIA INTERFACE
PWR
PWR
OUT
OUT
OUT
I/O
I/O
Page 10
IN
IN
Cost Competitive ARCNET (ANSI 878.1) Controller with 2K x 8 On-Chip RAM
In Normal Mode, these active low signals carry the
transmit data information, encoded in pulse format
as DIPULSE waveform. In Backplane Mode, the
nPULSE1 signal driver is programmable (push/pull
or open-drain), while the nPULSE2 signal provides
a clock with frequency of doubled data rate.
nPULSE1 is connected to a weak internal pull-up
resistor on the open/drain driver in backplane
mode.
This signal carries the receive data information from
the line transceiver.
Transmission Enable signal. Active polarity is
programmable through the nPULSE2 pin.
nPULSE2 floating before power-up;
nTXEN active low
nPULSE2 grounded before power-up;
nTXEN active high (this option is only available in
Back Plane mode)
An external crystal should be connected to these
pins. Oscillation frequency range is from 10 MHz to
20 MHz. If an external TTL clock is used instead, it
must be connected to XTAL1 with a 390ohm pull-up
resistor, and XTAL2 should be left floating.
+3.3 Volt power supply pins.
Ground pins.
Non-connection
DESCRIPTION
SMSC COM20019I 3.3V Rev.C