XR17L152 Datasheet, PDF (5/55 Pages) Exar Corporation – 3.3V PCI BUS DUAL UART

XR17L152
3.3V PCI BUS DUAL UART
REV. 1.1.0
áç
DISCONTINUED
PIN DESCRIPTIONS
NAME
XTAL1
PIN #
77
TYPE
DESCRIPTION
I Crystal or external clock input of up to data rate of 3.125Mbps at 33MHz 3.3V
and 8X sampling. See AC Characterization table. Caution: this input is not 5V
tolerant.
XTAL2
76
O Crystal or buffered clock output.
TMRCK
75
I 16-bit timer/counter external clock input.
ENIR
74
I Global Infrared mode enable (active high). During power up or reset, this pin
is sampled and if it is a logic high, both UARTs are set for infrared mode. Also,
the infrared mode bit, MCR[6], is set in both channels. Software can override
this pin thereafter and enable or disable infrared mode.
EN485#
65
I Global AutoRS485 half-duplex direction control enable (active low). During
power up or reset, this pin is sampled and if it is a logic high, both UARTs are
set for Auto RS485 Mode. Also, the Auto RS485 bit, FCTR[5], is set in both
channels. Software can override this pin thereafter and enable or disable it.
TEST#
VCC
79
54, 80
I Factory Test. Connect to VCC for normal operation.
PWR 5V or 3.3V power supply for the core logic.
VI/O
10, 22, 32, 43, PWR PCI bus I/O power supply. 3.3V ONLY (PCI 2.2 Compliance).
89, 100
GND
1, 11, 23, 33, PWR Power supply common, ground.
44, 53, 78, 88
NC
63, 64
No Connection.
NOTE: Pin type: I=Input, O=Output, I/O= Input/output, OD=Output Open Drain.
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