LTC1685 Linear Technology, LTC1685 Datasheet
LTC1685
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LTC1685 Summary of contents
Page 1
... Input resistance will remain 22k when the device is unpowered or disabled. The LTC1685 operates from a single 5V supply and draws only 7mA of supply current. , LTC and LT are registered trademarks of Linear Technology Corporation. ...
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... OUT = LOW V = – 10V (Note 5) OUT (Note 5) OUT ORDER PART TOP VIEW NUMBER LTC1685CS8 GND S8 PART MARKING S8 PACKAGE 8-LEAD PLASTIC SO 1685 = 125 C, = 150 MIN TYP MAX 1 ...
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... Note 3: All typicals are given for V Note 4: Guaranteed by design, but not tested. Note 5: Short-circuit current does not represent output drive capability. When the output detects a short-circuit condition, output drive current is significantly reduced (from hundreds 20mA max) until the short is removed. LTC1685 MIN TYP MAX UNITS 22 ...
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... LTC1685 W U TYPICAL PERFORMANCE CHARACTERISTICS Receiver Input CMRR 46.5 46.0 45.5 45.0 44.5 44.0 43.5 43 100k 1M FREQUENCY (Hz) 1685 G01 Receiver Propagation Delay vs Load Capacitance 105 205 LOAD CAPACITANCE (pF) 1685 G04 Receiver Propagation Delay vs Temperature –50 –25 ...
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... B outputs only High Low, DI will have no effect on A and B pins. Do not float. GND (Pin 5): Ground. A (Pin 6): Noninverting Receiver Input/Driver Output. B (Pin 7): Inverting Receiver Input/Driver Output. V (Pin 8): Positive Supply 5%. Bypass with DD 0.1 F ceramic capacitor. LTC1685 Driver Propagation Delay vs Capacitive Load 19 18.5 18.0 17 ...
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... LTC1685 CTIO TABLES Transmitting INPUTS LINE CONDITION Fault Fault Fault TEST CIRCUITS Figure 1. Driver DC Test Load DIFF Figure 3. Driver/Receiver Timing Test Circuit 6 Receiving OUTPUTS INPUTS ...
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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 LTC1685 1.5V 1 PHL t SKEW 90% 10% 1586 F05 0.5V 0. 1686 F06 2.5V t PLH 1686 F07 1 ...
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... The driver and receiver pair will have propagation delays that typically match to within 1ns. In clocked data systems, the low skew minimizes duty cycle distortion of the clock signal. The LTC1685 can be used at data rates of 52Mbps with less than 5% duty cycle distortion (depending on cable length). When a clock ...
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... For cables with the typical RS485 termination (no DC bias on the cable, such as Figure 10), the LTC1685 will auto- matically come out of short-circuit mode once the physical short has been removed. With cable terminations with a ...
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... Even at distances of 4000ft, 1Mbps data rates are possible using the LTC1685 and category 5 UTP. Figure 14a shows pulse propagated down 4000ft of category 5 UTP. Notice both the DC and the AC losses at the receiver input. ...
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... Power-Up Requirements The LTC1685 has unique short-circuit protection that shuts off the big output devices (and keeps them off) when a short is detected. When the LTC1685 is powered up with the driver outputs enabled (Figure 15 shows a typical connection), the part will power up in short-circuit mode. ...
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... INFORMATION parasitic board capacitance. This maintains the good matching characteristics of the low-to-high and high-to- low transitions of the LTC1685. Note that output “A” to output “B” capacitance should also be minimized. If routed adjacent to each other on the same layer, they should be separated by an amount at least as wide as the trace widths. If output “ ...