DC1747A-A Linear Technology, DC1747A-A Datasheet
DC1747A-A
Specifications of DC1747A-A
Related parts for DC1747A-A
DC1747A-A Summary of contents
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... Test and Measurement Equipment n Breaking RS232 Ground Loops n L, LT, LTC, LTM, Linear Technology, the Linear logo and µModule are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical applicaTion Isolated Dual RS232 µModule Transceiver 3.3V (LTM2882-3) ...
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LTM2882 absoluTe MaxiMuM raTings (Note GND .................................................. –0. GND .................................................... –0. GND2 ............................................... –0. CC2 Logic Inputs T1IN, T2IN, ON, DIN to GND ........–0.3V to ...
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T GND2 = 0V unless otherwise noted. L SYMBOL PARAMETER Supplies V Input Supply Range CC V Logic Supply Range L I Input Supply Current CC V Regulated Output ...
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LTM2882 swiTching characTerisTics temperature range, otherwise specifications are at T GND2 = 0V unless otherwise noted. L SYMBOL PARAMETER Maximum Data Rate (T1IN to T1OUT, T2IN to T2OUT) Maximum Data Rate (DIN to DOUT) Driver Driver Slew ...
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Typical perForMance characTerisTics 3.3V, and GND = GND2 = 0V Supply Current CC vs Temperature 30 NO LOAD V = 3.3V CC LTM2882 5.0V CC ...
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LTM2882 Typical perForMance characTerisTics 3.3V, and GND = GND2 = 0V Logic Input Threshold vs V Supply Voltage L 3.5 3.0 2.5 INPUT HIGH 2.0 1.5 1.0 0 ...
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Typical perForMance characTerisTics 3.3V, and GND = GND2 = 0V Surplus Current CC2 vs Temperature 300 250 200 150 V = 3.3V CC LTM2882-3 100 T1OUT AND T2OUT BAUD ...
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LTM2882 TesT circuiTs TIN ≤ 40ns ≤ 40ns r f ROUT DIN TIN ½V L TOUT 0V ...
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FuncTions LOGIC SIDE R2OUT (Pin A1): Channel 2 RS232 Inverting Receiver Output. Controlled through isolation barrier from receiver input R2IN. Under the condition of an isolation communi- cation failure R2OUT high impedance state. T2IN (Pin A2): ...
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LTM2882 block DiagraM 2.2µF GND ON DIN T1IN R1OUT T2IN R2OUT 10 5V REG 2.2µF DC/DC CONVERTER ISOLATED ISOLATED COMMUNI- COMMUNI- CATIONS CATIONS INTERFACE INTERFACE V CC2 2.2µF GND2 DE DOUT ...
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... The parasitic cable inductance along with the high Q char- acteristics of ceramic capacitors can cause substantial ringing which could exceed the maximum voltage ratings . CC2 and damage the LTM2882. Refer to Linear Technology Ap- supply DD plication Note 88, entitled “Ceramic Input Capacitors Can and V power ...
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LTM2882 applicaTions inForMaTion Channel Timing Uncertainty Multiple channels are supported across the isolation bound- ary by encoding and decoding of the inputs and outputs. The technique used assigns T1IN/R1IN the highest priority such that there is no jitter on the ...
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PCB Layout The high integration of the LTM2882 makes PCB layout very simple. However, to optimize its electrical isolation characteristics, EMI, and thermal performance, some layout considerations are necessary. • Under heavily loaded conditions V can exceed 300mA.Sufficient copper must be used ...
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... LTM2882 applicaTions inForMaTion Figure 7b. Low EMI Demo Board Layout (DC1747A), Top Layer Figure 7c. Low EMI Demo Board Layout (DC1747A), Inner Layer 1 14 TECHNOLOGY Figure 7a. Low EMI Demo Board Layout 2882fb ...
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... Figure 7d. Low EMI Demo Board Layout (DC1747A), Inner Layer 2 Figure 7e. Low EMI Demo Board Layout (DC1747A), Bottom Layer 60 DETECTOR = QuasiPeak R = 120kHz 300kHz BW SWEEP TIME = 17sec –10 DC1747A-A –20 DC1747A-B CISPR 22 CLASS 8 LIMIT –30 0 100 200 300 400 500 600 700 800 900 1000 FREQUENCY (MHz) 2882 F08 Figure 8 ...
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LTM2882 Typical applicaTions 3.3V (LTM2882-3) 5V (LTM2882- LTM2882 DIN T1IN 3.3k R1OUT T2IN 3.3k R2OUT GND GND2 Figure 9. Single Line Dual Half-Duplex Isolated Transceiver 3.3V (LTM2882-3) 5V (LTM2882-5) 1.8V V ...
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DescripTion Z bbb // 4.445 3.175 1.905 0.635 0.000 0.635 1.905 3.175 4.445 Z aaa LTM2882 2882fb 17 ...
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LTM2882 package DescripTion bbb 4.445 3.175 1.905 0.635 0.635 1.905 3.175 4.445 Z aaa 2882fb ...
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... H-Grade parts added. Reflected throughout the data sheet. Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... TO 25V T2OUT R2IN 3V TO 25V GND GND2 2882 F15 +V S LOGIC LEVEL FETS CMPT2369-LTV 1k 47pF R = 0.6/MAX CURRENT ILIM 2882 F16 Isolation with 1W Power RMS Isolator RMS LT 0311 REV B • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2010 –25V TO 0V –25V TO 0V 2882fb ...