LTC1686 Linear Technology, LTC1686 Datasheet
LTC1686
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LTC1686 Summary of contents
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... Receiver input resistance remains 22k when the device is unpowered or disabled. The LTC1686/LTC1687 operate from a single 5V supply and draw only 7mA of supply current. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
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... V DD OUT Operating Temperature Range .................... Storage Temperature Range ................ – 150 C + 0.5V Lead Temperature (Soldering, 10 sec)................. 300 ORDER PART NC 1 NUMBER 2 R LTC1686CS8 GND S8 PART MARKING GND 7 1686 14-LEAD PLASTIC SO T JMAX unless otherwise noted (Notes 2, 3). ...
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... S2 Closed, Figures 15pF, S1 Closed, Figures 15pF, S2 Closed, Figures (Note 15pF, Same Temperature (Note (Note (Note (Note 4) DD LTC1686/LTC1687 MIN TYP MAX 0.4 – – 200 200 500 3.2 3.3 3.4 ...
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... LTC1686/LTC1687 ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range. Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: All currents into the device pins are positive; all currents out of the device pins are negative ...
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... NC (Pins 1, 8, 13): No Connection. R (Pin 2): Receiver Output 300mV, then R will be high 300mV, then R will be low. RE (Pin 3): Receiver Enable low enables the receiver high forces receiver output into high impedance state. Do not float. LTC1686/LTC1687 Driver Propagation Delay vs Temperature ...
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... LTC1686/LTC1687 PIN FUNCTIONS DE (Pin 4): Driver Enable high enables the driver low will force the driver output into a high impedance state. Do not float. D (Pin 5): Driver Input. Controls the states of the Y and Z outputs when DE = high. Do not float. GND (Pins 6, 7): Ground. Y (Pin 9): Noninverting Driver Output. ...
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... PHL 0V INPUT Figure 7. Receiver Propagation Delays 1. 1MHz, t 3ns, t 3ns 2.5V OUTPUT NORMALLY LOW OUTPUT NORMALLY HIGH 2. Figure 8. Receiver Enable and Disable Times LTC1686/LTC1687 1.5V 1 PHL t SKEW 90% 10% 1686/87 F05 0.5V 0. 1686/87 F06 2.5V t PLH 1686/87 F07 1 ...
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... FAIL-SAFE FEATURES The LTC1686/LTC1687 have a fail-safe feature that guar- antees the receiver output logic HIGH state when the inputs are either shorted or left open (note that when inputs are left open, large external leakage currents might override the fail-safe circuitry) ...
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... C’s might give rise to ringing and even oscillation. All these conditions disappear once the device comes out of short-circuit mode. For cables with the typical RS485 termination (no DC bias on the cable, such as Figure 10), the LTC1686/LTC1687 will automatically come out of short-circuit mode once the physical short has been removed. Cable Termination ...
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... Figure 14b. 4000 Feet of Category 5 UTP 1Mbps Square Wave 1.6Mbps Over 8000 Feet (1.5 Miles) Category 5 UTP Using Repeaters The LTC1686/LTC1687 can be used as repeaters to extend the effective length of a high speed twisted-pair line. Figure 15a shows a three repeater configuration using 2000 feet segments of category 5 UTP ...
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... Note that single-ended operation might not reach maxi- mum speeds. LAYOUT CONSIDERATIONS A ground plane is recommended when using high fre- quency devices like the LTC1686/LTC1687. A 0.1 F ce- ramic bypass capacitor less than 0.25 inch away from the V pin is also recommended. DD ...
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... LTC1686/LTC1687 U U APPLICATIONS INFORMATION Long traces bounded and/or GND planes can add DD substantial parasitic capacitance. Parasitic capacitances on the receiver/driver outputs can also unduly slow down both the propagation delay and the rise/fall times. PACKAGE DESCRIPTION 0.010 – 0.020 45 (0.254 – 0.508) 0.008 – ...