Datasheet

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 ±   
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SLLS350L − APRIL 1999 − REVISED MARCH 2004
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
description/ordering information (continued)
Flexible control options for power management are available when the serial port is inactive. The
auto-powerdown feature functions when FORCEON is low and FORCEOFF
is high. During this mode of
operation, if the device does not sense a valid RS-232 signal, the driver outputs are disabled. If FORCEOFF
is set low, both drivers and receivers (except ROUT2B) are shut off, and the supply current is reduced to 1 µA.
Disconnecting the serial port or turning off the peripheral drivers causes the auto-powerdown condition to occur.
Auto-powerdown can be disabled when FORCEON and FORCEOFF
are high and should be done when driving
a serial mouse. With auto-powerdown enabled, the device is activated automatically when a valid signal is
applied to any receiver input. The INVALID
output is used to notify the user if an RS-232 signal is present at any
receiver input. INVALID
is high (valid data) if any receiver input voltage is greater than 2.7 V or less than −2.7 V
or has been between −0.3 V and 0.3 V for less than 30 µs. INVALID
is low (invalid data) if all receiver input
voltages are between −0.3 V and 0.3 V for more than 30 µs. Refer to Figure 5 for receiver input levels.
ORDERING INFORMATION
T
A
PACKAGE
†
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING
SOIC (DW)
Tube of 20 MAX3243CDW
MAX3243C
SOIC (DW)
Reel of 1000 MAX3243CDWR
MAX3243C
0°C to 70°C
SSOP (DB)
Tube of 50 MAX3243CDB
MAX3243C
0°C to 70°C SSOP (DB)
Reel of 2000 MAX3243CDBR
MAX3243C
TSSOP (PW)
Tube of 50 MAX3243CPW
MA3243C
TSSOP (PW)
Reel of 2000 MAX3243CPWR
MA3243C
SOIC (DW)
Tube of 20 MAX3243IDW
MAX3243I
SOIC (DW)
Reel of 1000 MAX3243IDWR
MAX3243I
−40°C to 85°C
SSOP (DB)
Tube of 50 MAX3243IDB
MAX3243I
−40°C to 85°C SSOP (DB)
Reel of 2000 MAX3243IDBR
MAX3243I
TSSOP (PW)
Tube of 50 MAX3243IPW
MB3243I
TSSOP (PW)
Reel of 2000 MAX3243IPWR
MB3243I
†
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are
available at www.ti.com/sc/package.
Function Tables
EACH DRIVER
INPUTS
OUTPUT
DIN FORCEON
FORCEOFF
VALID RIN
RS-232 LEVEL
OUTPUT
DOUT
DRIVER STATUS
X X L X Z Powered off
L H H X H
Normal operation with
H HH XL
Normal operation with
auto-powerdown disabled
L L H Yes H
Normal operation with
H LH YesL
Normal operation with
auto-powerdown enabled
L L H No Z
Powered off by
H L H No Z
Powered off by
auto-powerdown feature
H = high level, L = low level, X = irrelevant, Z = high impedance