Datasheet

6
LTC1387
FU CTIO TABLES
UU
Select Modes
SELECT INPUTS RECEIVER DRIVER
ON RXEN DXEN 485/232 RXA RXB DXY DXZ
1 0 0 0 Z Z Z Z ON OFF RS232 Mode, DX and RX Off
1 0 1 0 Z Z ON ON ON OFF RS232 Mode, DXY and DXZ On, RX Off
1 1 0 0 ON ON Z Z ON OFF RS232 Mode, DX Off, RXA and RXB On
1 1 1 0 ON ON ON ON ON OFF RS232 Mode, DXY and DXZ On,
RXA and RXB On
0 0 1 0 Z Z ON Z ON OFF RS232 Mode, DXY On, DXZ Off, RX Off
0 1 0 0 Z ON ON Z ON OFF RS232 Mode, DXY On,
DXZ Off, RXA Off, RXB On
0 1 1 0 ON ON ON ON ON ON RS232 Loopback Mode, DXY and DXZ On,
RXA and RXB On
0 0 0 X Z Z Z Z OFF OFF Shutdown, RS485 R
IN
1 0 0 1 Z Z Z Z ON OFF RS485 Mode, DX and RX Off
X 0 1 1 Z Z ON ON ON OFF RS485 Mode, DX On, RX Off
X 1 0 1 ON Z Z Z ON OFF RS485 Mode, DX Off, RX On
1 1 1 1 ON Z ON ON ON OFF RS485 Mode, DX On, RX On
0 1 1 1 ON Z ON ON ON ON RS485 Loopback Mode, DX On, RX On
RS232 Driver Mode
INPUTS
OUTPUTS
SELECTED 485/232 D CONDITIONS Y, Z
YES 0 0 No Fault 1
YES 0 1 No Fault 0
YES 0 X Thermal Fault Z
NO 0 X X Z
RS232 Receiver Mode
INPUTS
OUTPUTS
SELECTED 485/232 A, B R
A
, R
B
YES 0 0 1
YES 0 1 0
YES 0 Inputs Open 1
NO 0 X Z
RS485 Driver Slew Rate
INPUTS
OUTPUTS
DXEN 485/232 SLEW SLEW RATE
1 1 0 Slow
1 1 1 Fast
01X Z
RS485 Driver Mode
INPUTS OUTPUTS
DXEN 485/232 D CONDITIONS Z Y
1 1 0 No Fault 0 1
1 1 1 No Fault 1 0
1 1 X Thermal Fault Z Z
01XXZZ
RS485 Receiver Mode
INPUTS OUTPUTS
RXEN 485/232 B – A R
A
R
B
1 1 < –0.2V 0 Z
1 1 > 0.2V 1 Z
1 1 Inputs Open 1 Z
or Shorted to Ground
01 X ZZ
CHARGE PUMP LOOPBACK COMMENTS