xr16m681 Exar Corporation, xr16m681 Datasheet - Page 43

• Manufacturer Part Number: xr16m681
• Description: 1.62v To 3.63v Uart With 32-byte Fifo And Vlio Interface
• Manufacturer: Exar Corporation

REV. 1.0.0
For Power-Save, the UART internally isolates all of these inputs (except the modem inputs and Reset pins) therefore elimi-
nating any unnecessary external buffers to keep the inputs steady.
achieve minimum power drain, the voltage at any of the inputs of the M681 should NOT be lower than its VCC supply.
AC ELECTRICAL CHARACTERISTICS
TA = -40
S
XTAL1
T
T
ECLK
T
T
T
T
T
YMBOL
T
T
T
T
T
T
T
T
T
T
T
T
T
T
T
ECLK
LLAW
LLAR
WDO
T
MOD
RDV
SSR
CSL
WRI
LLA
WR
RSI
RRI
SSI
INT
AS
AH
RD
DY
DD
DS
DH
SI
O
TO
UART Crystal Frequency
External Clock Frequency
External Clock Time Period
Address Setup Time
Address Hold Time
Delay from CS# to LLA#/IOR#/IOW#
LLA# Strobe Width
IOR# Strobe Width
Delay from LLA# to IOR#
Delay from LLA# to IOW#
Read/Write Cycle Delay
Data Access Time
Data Disable Time
IOW# Strobe Width
Data Setup Time
Data Hold Time
Delay From IOW# To Output
Delay To Set Interrupt From MODEM
Input
Delay To Reset Interrupt From IOR#
Delay From Stop To Set Interrupt
Delay From IOR# To Reset Interrupt
Delay From Start To Interrupt
Delay From Initial INT Reset To
Transmit Start
Delay From IOW# To Reset Interrupt
Delay From Stop To Set RXRDY#
+85
O
C, V
CC IS
P
ARAMETER
1.62
TO
3.6V, 25
1.62V TO 3.63V UART WITH 32-BYTE FIFO AND VLIO INTERFACE
P
F
LOAD WHERE APPLICABLE
M
12
10
10
40
10
10
40
10
10
1.8V ± 10%
3
0
3
8
IN
L
43
IMITS
M
24
40
40
20
50
50
50
45
45
24
45
1
1
AX
SEE”POWER-SAVE FEATURE” ON PAGE 21.
M
10
25
10
10
25
10
2.5V ± 10%
7
8
2
0
8
2
8
IN
L
IMITS
M
24
64
20
10
50
50
50
45
45
24
45
1
1
AX
M
10
20
10
10
20
10
IN
3.3V ± 10%
6
6
2
0
6
2
8
L
IMITS
XR16M681
M
24
80
15
10
50
50
50
45
45
24
45
1
1
AX
U
MHz
MHz
Bclk
Bclk
Bclk
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
NIT
To