XRT16C854 Datasheet, PDF (43/54 Pages) Exar Corporation – 2.97V TO 5.5V QUAD UART WITH 128-BYTE FIFO

xr
REV. 3.0.1
XR16C854/854D
2.97V TO 5.5V QUAD UART WITH 128-BYTE FIFO
AC ELECTRICAL CHARACTERISTICS
TA=0^O TO 70^OC (-40^O TO +85^OC FOR INDUSTRIAL GRADE PACKAGE), VCC IS 2.97 TO 5.5V
SYMBOL
PARAMETER
LIMITS
3.3
MIN
MAX
LIMITS
5.0
MIN
MAX
UNIT
CONDITIONS
TSI Delay From Stop To Interrupt
45
40 ns
TINT Delay From Initial INT Reset To Transmit Start
8
24
8
24 Bclk
TWRI Delay From IOW# To Reset Interrupt
45
40 ns
TSSR Delay From Stop To Set RXRDY#
1
1 Bclk
TRR Delay From IOR# To Reset RXRDY#
45
40 ns
TWT Delay From IOW# To Set TXRDY#
45
40 ns
TSRT Delay From Center of Start To Reset TXRDY#
8
8 Bclk
TRST Reset Pulse Width
40
40
ns
N Baud Rate Divisor
1
2¹⁶-1
1
2¹⁶-1 ^-
Bclk Baud Clock
16X of data rate
bps
FIGURE 14. CLOCK TIMING
EXTERNAL
CLOCK
CLK
CLK
OSC
FIGURE 15. MODEM INPUT/OUTPUT TIMING FOR CHANNELS A-D
IO W #
IO W
RTS#
DTR#
A c tiv e
C h an ge o f state
T _{W DO}
C h a n g e o f sta te
CD#
CTS#
DSR#
IN T
IO R #
R I#
T _MOD
C h a n g e o f sta te
A c tive
A c tiv e
C ha n ge o f state
T _RSI
T _MOD
A c tiv e
A c tiv e
A c tiv e
A c tive
T_MOD
C ha n ge o f state
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