LTC2851 LINER [Linear Technology], LTC2851 Datasheet
LTC2851
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LTC2851 Summary of contents
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FeaTures Integrated, Logic-Selectable 120Ω Termination n Resistor 20Mbps Max Data Rate n No Damage or Latchup to ESD: ±15kV HBM n High Input Impedance Supports 256 Nodes n (C-, I-Grades) Operation Up to 105°C (LTC2859H) n 250kbps Low-EMI Mode n ...
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LTC2859/LTC2861 absoluTe maximum raTinGs Supply Voltage (V ) ................................... –0. Logic Input Voltages (RE, DE, DI, TE, SLO) .... –0. Interface I/ .......................................(V (A-B) or (B-A) with Terminator Enabled ..................6V Receiver ...
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T SYMBOL PARAMETER Driver |V | Differential Driver Output Voltage OD D|V | Change in Magnitude of Driver OD Differential Output Voltage for Complementary Output States V Driver Common Mode Output Voltage ...
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LTC2859/LTC2861 swiTchinG characTerisTics temperature range, otherwise specifications are at T SYMBOL PARAMETER Driver in Normal Mode (SLO HIGH) f Maximum Data Rate MAX Driver Input to Output PLHD PHLD Dt Driver Input to Output Difference PD |t ...
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TesT circuiTs Y GND + OR DI DRIVER – Figure 1. Driver DC Characteristics Y DI DRIVER DRIVER GND Z DE Figure 4. Driver Enable and Disable Timing Measurement ...
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LTC2859/LTC2861 TesT circuiTs ± RECEIVER B ± RECEIVER RECEIVER – ...
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Typical perFormance characTerisTics Receiver Skew vs Temperature 15pF –40 – 100 TEMPERATURE (°C) 285961 G01 R vs Temperature TERM 135 130 125 120 115 110 ...
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LTC2859/LTC2861 pin FuncTions (DD/DE/GN) RO (Pin 1): Receiver Output. If the receiver output is enabled (RE low) and A > 200mV, then RO will be high < 200mV, then RO will be low. If ...
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FuncTion Tables LTC2859 LOGIC INPUTS Receive with Term Transmit with Receive Transmit with Receive ...
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LTC2859/LTC2861 applicaTions inFormaTion Driver The driver provides full RS485 and RS422 compatibility. When enabled high, Y-Z is positive for the full duplex device (LTC2861) and A-B is positive for the half- duplex device (LTC2859). When the driver ...
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Receiver and Failsafe With the receiver enabled, when the absolute value of the differential voltage between the A and B pins is greater than 200mV, the state of RO will reflect the polarity of (A-B). The LTC2859/LTC2861 have ...
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LTC2859/LTC2861 applicaTions inFormaTion The integrated termination resistor has a high frequency response which does not limit performance at the maxi- mum specified data rate. Figure 12 shows the magnitude and phase of the termination impedance vs frequency. The termination resistor ...
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This can be avoided by maintaining normal logic levels on the pins and by slewing inputs through ...
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LTC2859/LTC2861 packaGe DescripTion Please refer to http://www.linear.com/designtools/packaging/ 3.55 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 0.25 ±0.05 2.38 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 TOP MARK (SEE NOTE 6) 0.200 REF NOTE: 1. DRAWING TO ...
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DescripTion Please refer to http://www.linear.com/designtools/packaging/ 3.60 ±0.05 2.20 ±0.05 1.70 ±0.05 0.25 ±0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 0.200 REF NOTE: 1. DRAWING ...
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LTC2859/LTC2861 packaGe DescripTion Please refer to http://www.linear.com/designtools/packaging/ .254 MIN .0165 ±.0015 RECOMMENDED SOLDER PAD LAYOUT .007 – .0098 (0.178 – 0.249) .016 – .050 (0.406 – 1.270) NOTE: 1. CONTROLLING DIMENSION: INCHES INCHES 2. DIMENSIONS ARE IN (MILLIMETERS) 3. DRAWING ...
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Rev C) REV DATE DESCRIPTION C 3/12 Added H-grade Order Information and Electrical Characteristics parameters Revised Receiver Input Resistance section Replaced Figure 12 Added Termination Resistor restriction information Information furnished by Linear Technology Corporation ...
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... PART NUMBER DESCRIPTION LTC2854/LTC2855 3.3V 20Mbps RS485/RS422 Transceivers with Integrated Switchable Termination LTC2856/LTC2857/ 5V 20Mbps and Slew Rate Limited 15kV RS485/RS422 LTC2858 Transceivers LTC2850/LTC2851/ 3.3V 20Mbps RS485/RS422 Transceivers LTC2852 LTC2862/LTC2863/ ±60V Fault Protected 3V to 5.5V RS485/RS422 Transceivers LTC2864/LTC2865 LTM2881 Complete 3.3V Isolated RS485/RS422 µModule + Power LTC485 ...