LTC1968CMS8 Linear Technology, LTC1968CMS8 Datasheet
LTC1968CMS8
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LTC1968CMS8 Summary of contents
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... A low power shutdown mode reduces supply current to 0.1µA. The LTC1968 is packaged in the space-saving MSOP pack- age, which is ideal for portable applications. , LTC and LT are registered trademarks of Linear Technology Corporation. Protected under U.S. Patent Numbers 6,359,576, 6,362,677 and 6,516,291 + C ...
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... Fundamental, 200mV RMS 60Hz Fundamental, 200mV RMS Accuracy = 1% (Note 14) Average, Differential (Note 12) Average, Common Mode (Note 12) (Note 13) (Note ORDER PART NUMBER LTC1968CMS8 8 ENABLE + LTC1968IMS8 OUT RTN 5 V OUT MS8 PART MARKING = 220°C/ W LTAFG JA = 10µF, V ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are T unless otherwise noted. 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 Supply Rejection Frequency Response ...
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LTC1968 W U TYPICAL PERFOR A CE CHARACTERISTICS Gain and Offset vs Input Common Mode Voltage 0.5 50mV ≤ V ≤ 350mV IN 0.4 0.3 0.2 0.1 GAIN ERROR 0 V OOS –0.1 V IOS –0.2 –0.3 –0.4 –0.5 0 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Performance vs Crest Factor 201.0 200mV SCR WAVEFORMS RMS 200 10µF AVE O.1%/DIV 200.6 20Hz 200.4 200.2 1kHz 200.0 10kHz 199.8 60Hz 199.6 199.4 199.2 199 CREST ...
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LTC1968 W U TYPICAL PERFOR A CE CHARACTERISTICS Bandwidth to 500kHz 202 0.5%/DIV C = 10µF AVE 201 V = 200mV IN RMS 200 199 198 197 196 195 100 200 300 500 0 400 INPUT FREQUENCY (kHz) 1968 G14 ...
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CTIO S GND (Pin 1): Ground. The 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 5): Output Voltage. ...
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LTC1968 U U APPLICATIO S I FOR ATIO currents. The power delivered to the load depends on the firing angle, as well as any parasitic losses such as switch “ON” voltage drop. Real circuit waveforms will also typi- cally have ...
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U U APPLICATIO S I FOR ATIO α V OUT ∆-Σ REF V IN ±1 Figure 4. Topology of LTC1968 The ∆Σ modulator has a single-bit output whose average duty cycle (D) will be proportional to the ...
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LTC1968 U U APPLICATIO S I FOR ATIO Because this peak has energy (proportional to voltage 2 squared) that is 16 times (4 ) the energy of the RMS value, the peak is necessarily present for at most 6.25% (1/16) ...
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U U APPLICATIO S I FOR ATIO 0 –0.2 –0.4 –0 220µ 100µF –0.8 –1.0 –1.2 –1.4 –1.6 –1.8 –2.0 1 Figure 8. Peak Error vs Input Frequency with One Cap Averaging because of the computation ...
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LTC1968 U U APPLICATIO S I FOR ATIO Input Connections The LTC1968 input is differential and DC coupled. The LTC1968 responds to the RMS value of the differential voltage between Pin 2 and Pin 3, including the DC portion of ...
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U U APPLICATIO S I FOR ATIO Output Connections The LTC1968 output is differentially, but not symmetri- cally, generated. That is to say, the RMS value that the LTC1968 computes will be generated on the output (Pin 5) relative to ...
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LTC1968 U U APPLICATIO S I FOR ATIO 100mV to 110mV (+10%) and back (–10%), the step responses are essentially the same as a standard expo- nential rise and decay between those two levels. In such cases, the time constant ...
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... LTC1968 V . The table inset in Figure 12 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 LTC1968 output, includ- ing ground, which in single supply applications is the nega- tive supply ...
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LTC1968 U U APPLICATIO S I FOR ATIO somewhat lower (≈0.7 • 1.27 ≈ 0.9Hz) than with 10µF alone. To adjust the bandwidth of either of them, simply scale all the capacitors by a common multiple, and leave the resistors ...
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U U APPLICATIO S I FOR ATIO 100µF –0.2 –0.4 –0 47µ 22µF –0.8 –1.0 –1.2 –1.4 –1.6 –1.8 –2.0 1 Figure 16. Peak Error vs Input Frequency with Buffered Post Filter 0 ...
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LTC1968 U U APPLICATIO S I FOR ATIO 0.22µ 0.47µ 1µF 1 0.1 0.01 0 0.1µ 0.22µ 0.47µF 1 0.1 0.01 0.1 Crest factor, which is ...
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U U APPLICATIO S I FOR ATIO waveform dynamics and the type of filtering used. The above method is conservative for some cases and about right for others. The LTC1968 works well with signals whose crest factor ...
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LTC1968 U U APPLICATIO S I FOR ATIO (√(5mV AC) + (0.4mV DC) OUT = 5.221mV = 5mV + 4.42% As can be seen, the gain term dominates with large inputs, while the offset terms become significant ...
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U U APPLICATIO S I FOR ATIO This allows each sample to settle to within 46ppm and it is these samples that are used to compute the RMS value. This is a much higher accuracy than the LTC1968 conver- sion ...
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LTC1968 U U APPLICATIO S I FOR ATIO LTC1968 5 31 OUTPUT C AVE 6 30 OUT RTN Figure 21a. Interfacing to DVM/DPM ADC LTC1968 LTC2420 5 3 OUTPUT V SDO IN C AVE 6 4 OUT RTN GND SCK ...
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U U APPLICATIO S I FOR ATIO The trade-off here is that on the one hand, the DC error is input frequency dependent calibration signal fre- quency high enough to make the DC error negligible should be used. ...
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LTC1968 U U APPLICATIO S I FOR ATIO TROUBLESHOOTING GUIDE Top Ten LTC1968 Application Mistakes 1. Circuit won’t work–Dead On Arrival–no power drawn. – Probably forgot to enable the LTC1968 by pulling Pin 8 low. Solution: Tie Pin 8 to ...
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U U APPLICATIO S I FOR ATIO 7. Output is noisy with >200kHz inputs. – This is a fundamental characteristic of this topol- ogy. The LTC1968 is designed to work very well with inputs of 100kHz or less. It works ...
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LTC1968 PLIFIED SCHE ATIC + V GND C1 IN1 2nd ORDER ∆Σ MODULATOR IN2 BIAS CONTROL U TYPICAL APPLICATIO S 5V Single Supply, Differential, AC-Coupled RMS-to-DC Converter LTC1968 AC INPUTS ...
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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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... Micropower, No Latency ∆Σ LTC2420 20-bit, Micropower, No Latency ∆Σ ADC in SO-8 LTC2422 2-Channel, 20-bit, Micropower, No Latency ∆Σ ADC No Latency ∆Σ trademark of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...