LTC1966CMS8 Linear Technology, LTC1966CMS8 Datasheet

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... MSOP package which is ideal for portable applications. APPLICATIO S True RMS Digital Multimeters and Panel Meters True RMS Measurements , LTC and LT are registered trademarks of Linear Technology Corporation. Protected under U.S. Patent Numbers 6,359,576 and 6,362,677 Quantum Leap in Linearity Performance 0.2 0 – ...

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... Fundamental, 200mV (Note 11) RMS Average, Differential (Note 12) Average, Common Mode (Note 12) (Note 13) Accuracy = 1% (Note 14) V Supply (Note Supply (Note ORDER PART NUMBER TOP VIEW 8 ENABLE LTC1966CMS8 LTC1966IMS8 6 OUT RTN 5 V OUT MS8 PACKAGE MS8 PART MARKING LTTG = 150 C, = 220 LTTH = 0V 200mV ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are 0.5V unless otherwise noted. ENABLE SYMBOL PARAMETER Output Characteristics OVR Output Voltage Range Z Output Impedance OUT CMRRO Output Common Mode Rejection V Maximum Differential Output Swing OMAX PSRRO Power ...

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LTC1966 ELECTRICAL CHARACTERISTICS Note 11: High speed automatic testing cannot be performed with 60Hz inputs. The LTC1966 is 100% tested with DC stimulus. Correlation tests have shown that the performance limits above can be guaranteed with the additional testing being ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Gain and Offsets vs Temperature 0 0 GND SS 0.3 0.2 0.1 0 –0.1 –0.2 –0.3 –0.4 –0.5 –50 – TEMPERATURE ( C) Gain and ...

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LTC1966 W U TYPICAL PERFOR A CE CHARACTERISTICS Gain and Offset vs V Supply DD 0 GND SS 0.4 0.3 V IOS 0.2 0.1 GAIN ERROR 0 –0.1 V OOS –0.2 –0.3 –0.4 –0.5 2.5 3.0 3.5 4.0 ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Input Signal Bandwidth 202 200 198 196 194 192 190 188 186 1%/DIV 184 C = 2.2 F AVE 182 1 10 100 1000 INPUT FREQUENCY (kHz) 1966 G20 Common Mode Rejection Ratio ...

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LTC1966 CTIO S GND (Pin 1): Ground. A power return pin. IN1 (Pin 2): Differential Input. DC coupled (polarity is irrelevant). IN2 (Pin 3): Differential Input. DC coupled (polarity is irrelevant). V (Pin 4): Negative ...

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U U APPLICATIO S I FOR ATIO READ RMS-TO-DC CONVERSION CONTACT LTC BY PHONE OR AT www.linear.com AND GET SOME NOW READ THE TROUBLESHOOTING GUIDE. IF NECESSARY, CALL LTC FOR APPLICATIONS SUPPORT CONTACT LTC AND PLACE YOUR ORDER W U ...

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LTC1966 U U APPLICATIO S I FOR ATIO RMS-TO-DC CONVERSION Definition of RMS RMS amplitude is the consistent, fair and standard way to measure and compare dynamic signals of all shapes and sizes. Simply stated, the RMS amplitude is the ...

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U U APPLICATIO S I FOR ATIO How an RMS-to-DC Converter Works Monolithic RMS-to-DC converters use an implicit com- putation to calculate the RMS value of an input signal. The fundamental building block is an analog multiply/divide used as shown ...

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LTC1966 U U APPLICATIO S I FOR ATIO More detail of the LTC1966 inner workings is shown in the Simplified Schematic towards the end of this data sheet. Note that the internal scalings are such that the duty cycle is ...

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U U APPLICATIO S I FOR ATIO DESIGN COOKBOOK The LTC1966 RMS-to-DC converter makes it easy to implement a rather quirky function. For many applications all that will be needed is a single capacitor for averaging, appropriate selection of the ...

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LTC1966 U U APPLICATIO S I FOR ATIO 0 –0.2 –0 100 F –0.6 –0 –1.0 –1.2 –1.4 –1.6 –1.8 –2.0 1 Figure 8. Peak Error vs Input Frequency with ...

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U U APPLICATIO S I FOR ATIO For single-ended DC-coupled applications, simply con- nect one of the two inputs (they are interchangeable) to the signal, and the other to ground. This will work well for dual supply configurations, but for ...

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LTC1966 U U APPLICATIO S I FOR ATIO In any configuration, the averaging capacitor should be connected between Pins 5 and 6. The LTC1966 RMS-DC output will be a positive voltage created at V with respect to OUT RTN (Pin ...

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U U APPLICATIO S I FOR ATIO 120 AVE 100 0.1 0.2 0.3 TIME (SEC) Figure 11a. LTC1966 Rising Edge with 0 0.22 ...

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... LTC1966 V . The table inset in Figure 13 shows OOS these errors for four of Linear Technology’s op amps. A second disadvantage is that the op amp output has to operate over the same range as the LTC1966 output, includ- ing ground, which in single supply applications is the nega- tive supply ...

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U U APPLICATIO S I FOR ATIO ( 0.7 • 1.8 1.3Hz) than with 1 F alone. To adjust the bandwidth of either of them, simply scale all the capaci- tors by a common multiple, and leave the resistors unchanged. ...

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LTC1966 U U APPLICATIO S I FOR ATIO 0 –0 –0.4 –0 4.7 F –0.8 –1.0 –1.2 –1.4 –1.6 –1.8 –2.0 1 Figure 17. Peak Error vs Input Frequency with Buffered Post Filter 0 ...

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U U APPLICATIO S I FOR ATIO 0 0. 0.1 0. 0.1 0.01 0.1 frequency. So with waveforms, ...

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LTC1966 U U APPLICATIO S I FOR ATIO Obviously, the effect of crest factor is somewhat simplified above given the factor of two difference based on a subjective description of the waveform type. The results will vary somewhat based on ...

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U U APPLICATIO S I FOR ATIO (50mV AC) + (0.2mV DC) OUT = 50.150mV = 50mV + 0.301 (5mV AC) + (0.2mV DC) OUT = 5.109mV = 5mV + 2.18% As ...

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LTC1966 U U APPLICATIO S I FOR ATIO small, 2.5pF • 100k = 250ns, and during the 2.5 s period devoted to sampling, ten time constants elapse. This allows each sample to settle to within 46ppm and it is these ...

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U U APPLICATIO S I FOR ATIO LTC1966 5 31 OUTPUT C AVE 6 30 OUT RTN Figure 22a. Interfacing to DVM/DPM ADC LTC1966 LTC2420 5 3 OUTPUT V SDO IN C AVE 6 4 OUT RTN GND SCK CS ...

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LTC1966 U U APPLICATIO S I FOR ATIO The best frequency for the calibration signal is roughly ten times the – 0.1% DC error frequency. For 1 F, – 0.1% DC error occurs at 8Hz, so 80Hz is a good ...

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U U APPLICATIO S I FOR ATIO TROUBLESHOOTING GUIDE Top Ten LTC1966 Application Mistakes 1. Circuit won’t work–Dead On Arrival–no power drawn. – Probably forgot to enable the LTC1966 by pulling Pin 8 low. Solution: Tie Pin 8 to Pin ...

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LTC1966 U U APPLICATIO S I FOR ATIO 7. Output is noisy with >10kHz inputs. – This is a fundamental characteristic of this topol- ogy. The LTC1966 is designed to work very well with inputs of 1kHz or less. It ...

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U TYPICAL APPLICATIO S 5V Supplies, Differential, DC-Coupled RMS-to-DC Converter LTC1966 IN1 V INPUTS OUT (1V PEAK IN2 OUT RTN DIFFERENTIAL) V GND EN SS 1966 TA03 –5V AC CURRENT 75A MAX 50Hz TO ...

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LTC1966 PLIFIED SCHE ATIC V DD GND IN1 2nd ORDER IN2 BIAS CONTROL MODULATOR – – C12 C9 ...

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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...

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... A Max, Single Supply Precision Dual Op Amp LTC2402 2-Channel, 24-bit, Micropower, No Latency LTC2420 20-bit, Micropower, No Latency LTC2422 2-Channel, 20-bit, Micropower, No Latency No Latency is a trademark of Linear Technology Corporation. Linear Technology Corporation 32 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 0.1 F X7R –2.5V ...