LT1791 LINER [Linear Technology], LT1791 Datasheet
LT1791
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LT1791 Summary of contents
Page 1
... On-chip ESD protection elimi- nates need for external protection devices. The LT1785/LT1785A are available in 8-lead DIP and SO packages and the LT1791/LT1791A in 14-lead DIP and SO packages. , LTC and LT are registered trademarks of Linear Technology Corporation. CC1 ...
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... JMAX JA Consult factory for Military grade parts (Note 1) Operating Temperature Range LT1785C/LT1791C/ LT1785AC/LT1791AC ............................. LT1785I/LT1791I ............................... – Storage Temperature Range ................ – 150 C Lead Temperature (Soldering, 10 sec)................. 300 ORDER PART NUMBER LT1785CN8 NC 1 LT1785CS8 RO ...
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... Change in Magnitude of Driver Common Mode OC Output Voltage for Complementary Output States V Input High Voltage IH V Input Low Voltage IL I Input Current IN1 I Input Current (A, B); (LT1791 or LT1785 with IN2 DE = 0V) V Differential Input Threshold Voltage for Receiver TH V Receiver Input Hysteresis TH V Receiver Output High Voltage OH V ...
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... LT1785/LT1785A LT1791/LT1791A U SWITCHI G CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are SYMBOL PARAMETER t Driver Input to Output PLH t Driver Input to Output PHL t Driver Output to Output SKEW Driver Rise or Fall Time Driver Enable to Output High ...
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... DE: Driver Output Enable. TTL level logic input. A logic high on DE enables normal operation of the driver outputs (Y and Z on LT1791, A and B on LT1785). A logic low level at DE places the driver output pins into a high impedance LT1785/LT1785A ...
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... B receiver forces a receiver output low. Receiver inputs A and B are protected against voltage faults between 60V. The high input impedance allows up to 128 LT1785 or LT1791 transceivers on one RS485 data bus. The LT1785A/LT1791A have guaranteed receiver input thresholds –200mV < V guaranteed high state for 0V inputs ...
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... Hi-Z Hi OUTPUT Hi-Z * 0mV for LT1791A 125kHz, t 10ns, t 10ns 1. PLH t SKEW O 90 V(A) – V(B) DIFF 10 Figure 5. Driver Propagation Delays LT1785/LT1785A LT1791/LT1791A S1 500 Figure 4. Driver Timing Test Load INPUTS ...
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... Figure 8. Receiver Enable and Disable Times W U cally – 12.5V. Replacement of standard RS485 transceiver components with the LT1785 or LT1791 devices eliminates field failures due to overvoltage faults or the use of costly external protection devices. The limited overvoltage tolerance of CMOS RS485 transceivers makes implementation of effective external protection networks difficult without interfering with proper data network performance within the – ...
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... The LT1785/LT1791 I/O pins have on-chip ESD protection circuitry to eliminate field failures caused by discharges to exposed ports and cables in application environments. The LT1785 pins A and B and the LT1791 driver output pins Y and Z are protected to IEC-1000-4-2 level 2. These pins will survive multiple ESD strikes of 15kV air dis- charge or 4kV contact discharge ...
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... DWG # 05-08-1610) 0.053 – 0.069 (1.346 – 1.752) 0.004 – 0.010 (0.101 – 0.254) 0.014 – 0.019 0.050 (0.355 – 0.483) (1.270) TYP LT1791 1785/91 F09 0.400* (10.160) MAX 0.255 0.015* (6 ...
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... TYP 0.014 – 0.019 (0.355 – 0.483) LT1785/LT1785A LT1791/LT1791A 0.770* (19.558) MAX 0.045 – 0.065 (1.143 – 1.651) 0.065 (1 ...
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... LT1785/LT1785A LT1791/LT1791A U TYPICAL APPLICATIONS 120 LT1785 LT1785 Figure 11. RS485 Network with 120V AC Line Fault Protection RELATED PARTS PART NUMBER DESCRIPTION LTC485 Low Power RS485 Interface Transceiver LTC491 Differential Driver and Receiver Pair ...