ST16C450
UNIVERSAL ASYNCHRONOUS
RECEIVER/TRANSMITTER (UART)
September2003
GENERAL DESCRIPTION
PLCC Package
The ST16C450 is a universal asynchronous receiver
and transmitter. The ST16C450 is an improved ver-
sion of the NS16450 UART with higher operating
speed and lower access time. A programmable baud
rate generator is provided to select transmit and
receive clock rates from 50 Bps to 1.5 Mbps.
TheST16C450onboardstatusregisters providesthe
error conditions, type and status of the transfer
operation being performed. Included is complete
MODEM control capability, and a processor interrupt
system that may be software tailored to the user’s
requirements. The ST16C450 provides internal loop-
back capability for on board diagnostic testing.
The ST16C450 is available in 40 pin PDIP, 44 pin
PLCC, and 48 pin TQFP packages. It is fabricated in
an advanced CMOS process to achieve low drain
power and high speed requirements.
7
39
38
37
36
35
34
33
32
31
30
29
D5
D6
RESET
-OP1
-DTR
-RTS
-OP2
N.C.
INT
8
9
D7
10
11
12
13
14
15
16
17
RCLK
RX
N.C.
ST16C450CJ44
TX
CS0
N.C.
A0
CS1
-CS2
-BAUDOUT
A1
A2
FEATURES
• Pin to pin and functionally compatible to the Indus-
tryStandard16450
• 2.97 to 5.5 volt operation
• 1.5Mbpstransmit/receiveoperation(24MHz)
• Programmable word lengths (5, 6, 7, 8)
• Even, odd, force, or no parity generation and
detection
• Independent transmit and receive control
• Standard modem interface
• Low operating current ( 1.2mA typ.)
ORDERING INFORMATION
Part number
Package
Operating temperature
Device Status
ST16C450CP40
ST16C450CJ44
ST16C450CQ48
ST16C450IP40
ST16C450IJ44
ST16C450IQ48
40-Lead PDIP
44-Lead PLCC 0° C to + 70° C
48-Lead TQFP 0° C to + 70° C
40-Lead PDIP
44-Lead PLCC -40° C to + 85° C
48-Lead TQFP -40° C to + 85° C
0° C to + 70° C
Active. See the ST16C450CQ48 for new designs.
Active
Active
Active. See the ST16C450IQ48 for new designs.
Active
Active
-40° C to + 85° C
Rev.4.20
EXAR Corporation, 48720 Kato Road, Fremont, CA 94538 • (510) 668-7000 • FAX (510) 668-7017