
EXAR
Corporation, 48720 Kato Road, Fremont, CA 94538
(510) 668-7000
FAX (510) 668-7017
XR68C92/192
Rev. P2.10
PLCC Package
DUAL UNIVERSAL ASYNCHRONOUS
RECEIVER AND TRANSMITTER
DESCRIPTION
The XR68C92/192 is a Dual Universal Asynchronous Receiver and Transmitter with 8 (XR68C92) or 16 (XR68C192)
bytes of transmit and receive FIFOs. The XR68C92/192 is pin-to-pin and functionally compatible to the XR68C681
and Philips SCC68681 UART with additional features. The operating speed of the receiver and transmitter can be
selected independently from a table of twenty four fixed baud rates, a 16X clock derived from a programmable counter/
timer, or an external 1X or 16X clock. The baud rate generator and counter/timer can operate directly from a crystal
or from external clock input. The XR68C92/192 provides a power down mode in which the oscillator is stopped but
the register contents are retained. The XR68C92/192 s fabricated n an advanced CMOS process to achieve ow power
and high speed requirements.
FEATURES
Pin to pin and functionally compatible to XR68C681
and SCC68692
Full duplex transmit and receive operation
8 bytes of transmit/receive FIFOs (XR68C92)
16 bytes of transmit/receive FIFOs (XR68C192)
Programmable character lengths (5, 6, 7, 8)
Parity, framing, and over run error detection
Programmable 16-bit timer/counter
On-chip crystal oscillator
Single interrupt output with eight selectable interrupt-
ing conditions
External 1X or 16X clock
Data rate up to 1Mbps
Independent transmit and receive baud rates from
50bps to 230.4kbps
6 General purpose inputs
8 General purpose outputs
TTL compatible inputs, outputs
4 Transmit/receive trigger levels
Watch dog timer
Multi-drop mode compatible with 8051 nine bit mode
3.3 or 5 volts operation
Loopback modes
Power down mode
ORDERING INFORMATION
Part number
XR68C92CP
XR68C92CJ
XR68C92CV
XR68C92IP
XR68C92IJ
XR68C92IV
Pins Package
40
PDIP
44
PLCC
44
TQFP
40
PDIP
44
PLCC
44
TQFP
Operating temperature
0° C to + 70° C
0° C to + 70° C
0° C to + 70° C
-40° C to + 85° C
-40° C to + 85° C
-40° C to + 85° C
Part number
XR68C192CP
XR68C192CJ
XR68C192CV
XR68C192IP
XR68C192IJ
XR68C192IV
Pins PackageOperating temperature
40
PDIP
44
PLCC
44
TQFP
40
PDIP
44
PLCC
44
TQFP
0° C to + 70° C
0° C to + 70° C
0° C to + 70° C
-40° C to + 85° C
-40° C to + 85° C
-40° C to + 85° C
May 2000
www.exar.com
6
5
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1
4
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4
4
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9
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39
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35
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1
1
2
2
2
2
2
2
2
2
2
A4
IP0
R/-W
-DTACK
RXB
N.C.
TXB
OP1
OP3
OP5
OP7
-CS
-RESET
XTAL2
XTAL1
RXA
N.C.
TXA
OP0
OP2
OP4
OP6
D
D
D
D
G
N
-
D
D
D
D
A
I
A
I
A
N
V
I
I
-
I
XR68C92
XR68C192