LTC1387 Linear Technology, LTC1387 Datasheet
LTC1387
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LTC1387 Summary of contents
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... A loop back mode allows the driver outputs to be connected back to the receiver inputs for diagnostic self-test. The LTC1387 is available in 20-pin plastic SSOP and SW packages. , LTC and LT are registered trademarks of Linear Technology Corporation. 19 ...
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... .......................... 30 sec DD EE Operating Temperature Range LTC1387C .............................................. LTC1387I ........................................... – Storage Temperature Range ................ – 150 C Lead Temperature (Soldering, 10 sec)................ 300 C DC ELECTRICAL CHARACTERISTICS 5V 0.1 F (Notes 2, 3), unless otherwise noted SYMBOL ...
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... C = 15pF L L Figures 5, 11 Figures 5, 11 Figures 100pF L L Figures 100pF L L Figures 100pF L L Figures 100pF L L LTC1387 MIN TYP MAX UNITS – 0.20 0. – 0 0.8 V 2 ...
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... LTC1387 AC ELECTRICAL CHARACTERISTICS 5V 0.1 F (Notes 2, 3), unless otherwise noted SYMBOL PARAMETER RS485 Mode (Fast Slew Rate DXEN = High, 485/232 = High, SLEW = High) t Driver Enable to Output Low ZL t Driver Enable to Output High ZH t Driver Disable from Low ...
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... Receiver A Output. Output A in RS232 mode; A the differential receiver output in RS485 mode. V (Pin 18): Positive Supply. 4.75V CC Requires an external 0.1 F bypass capacitor to ground. – C2 (Pin 19): Commutating Capacitor C2 Negative Termi- nal. Requires an external 0.1 F capacitor between Pins 19 and 20 (Pin 20): Commutating Capacitor C2 Positive Terminal. LTC1387 V 5.25V ...
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... LTC1387 CTIO TABLES Select Modes SELECT INPUTS RECEIVER ON RXEN DXEN 485/232 RXA RXB ...
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... EE 500 DR OUT 15pF C L LTC1387 • F02 LTC1387 • F03 Figure 3. RS485 Driver Output Enable/Disable Timing Test Load 1k RECEIVER OUT C L 15pF LTC1387 • F05 LTC1387 • F06 Figure 6. Receiver Output Enable/Disable Timing Test Load ...
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... INPUT PLH OUTPUT 1.5V Figure 9. RS485 Receiver Propagation Delays 1.5V t PHL 0V Figure 10. RS232 Driver Propagation Delays 1.5V t PHL 90% 50% 10 SKEW LTC1387 • F07 1. 0. 0.5V LTC1387 • F08 0V t PHL 1.5V LTC1387 • F09 1.5V t PLH LTC1387 • F10 0V ...
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... PPLICATI S I FOR ATIO Basic Theory of Operating The LTC1387 is a single 5V supply, single-port logic reconfigurable RS485/RS232 transceiver with an onboard charge pump. The interface port offers a flexible combina- tion of an RS485 driver and an RS485 receiver or two RS232 drivers and two RS232 receivers. The RS485 transceiver and the RS232 transceivers are designed to share the same I/O pins ...
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... A loopback mode enables internal connections from driver outputs to receiver inputs for self-test. The driver outputs are not isolated from the external loads during loopback. The charge pump generates boosted positive voltage V and negative voltage V single 5V V 0.1 F capacitors. LTC1387 RS232 RS485 ...
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... RX2 CONTROLLER D Y DX1 D /SLEW Z DX2/SLEW RXEN RXEN DXEN DXEN 485/232 MODE LTC1387 RS485 RS485 SHUTDOWN TRANSMIT MODE RECEIVE MODE RXEN = 0 RXEN = 1 RXEN = 0 DXEN = 1 DXEN = 0 DXEN = 0 MODE = 1 MODE = 1 MODE = 0 RS232 RS485 SHUTDOWN MODE MODE MODE RXEN = 1 RXEN = 1 ...
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... LTC1387 PACKAGE DESCRIPTION 0.205 – 0.212** (5.20 – 5.38) 0.005 – 0.009 0.022 – 0.037 (0.55 – 0.95) (0.13 – 0.22) * DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 0.291 – ...