LTC1387 Linear Technology, LTC1387 Datasheet - Page 6

• Manufacturer Part Number: LTC1387
• Description: Single 5V RS232/RS485 Multiprotocol Transceiver
• Manufacturer: Linear Technology

FU CTIO TABLES
LTC1387
Select Modes
RS232 Driver Mode
6
RS232 Receiver Mode
SELECTED
ON RXEN DXEN 485/232 RXA RXB
1
1
1
1
0
0
0
0
1
X
X
1
0
SELECTED
YES
YES
YES
NO
U
YES
YES
YES
NO
SELECT INPUTS
0
0
1
1
0
1
1
0
0
0
1
1
1
485/232
INPUTS
0
1
0
1
1
0
1
0
0
1
0
1
1
0
0
0
0
U
485/232
INPUTS
0
0
0
0
0
0
0
0
0
0
0
X
1
1
1
1
1
D
0
1
X
X
ON
ON
ON
ON
ON
ON
RECEIVER
Z
Z
Z
Z
Z
Z
Z
Thermal Fault
Inputs Open
CONDITIONS
ON
ON
ON
ON
Z
Z
Z
Z
Z
Z
Z
Z
Z
No Fault
No Fault
A, B
X
0
1
X
DXY
ON
ON
ON
ON
ON
ON
ON
ON
Z
Z
Z
Z
Z
DRIVER
DXZ
ON
ON
ON
ON
ON
ON
Z
Z
Z
Z
Z
Z
Z
OUTPUTS
OUTPUTS
R
Y, Z
CHARGE PUMP LOOPBACK
A
1
0
Z
Z
, R
1
0
1
Z
B
OFF
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON
RS485 Driver Slew Rate
RS485 Driver Mode
RS485 Receiver Mode
DXEN
DXEN
1
1
1
0
RXEN
1
1
0
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
ON
ON
1
1
1
0
485/232
INPUTS
485/232
INPUTS
1
1
1
1
1
1
1
485/232
1
1
1
1
INPUTS
RS232 Loopback Mode, DXY and DXZ On,
RS232 Mode, DX Off, RXA and RXB On
RS232 Mode, DXY and DXZ On, RX Off
RS232 Mode, DXY On, DXZ Off, RX Off
RS485 Loopback Mode, DX On, RX On
SLEW
RS232 Mode, DXY and DXZ On,
X
0
1
RS232 Mode, DX and RX Off
RS485 Mode, DX and RX Off
RS485 Mode, DX On, RX Off
RS485 Mode, DX Off, RX On
RS485 Mode, DX On, RX On
D
X
X
0
1
DXZ Off, RXA Off, RXB On
or Shorted to Ground
RS232 Mode, DXY On,
Shutdown, RS485 R
RXA and RXB On
RXA and RXB On
Inputs Open
COMMENTS
Thermal Fault
< – 0.2V
CONDITIONS
> 0.2V
B – A
No Fault
No Fault
X
X
SLEW RATE
OUTPUTS
Slow
Fast
IN
Z
R
Z
0
1
Z
Z
0
1
1
Z
OUTPUTS
OUTPUTS
A
R
Y
1
0
Z
Z
Z
Z
Z
Z
B