AD698AP Analog Devices Inc, AD698AP Datasheet
AD698AP
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AD698AP Summary of contents
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... LVDT interfacing. The benefits of this new cir- cuit are: no adjustments are necessary; temperature stability is improved; and transducer interchangeability is improved. The AD698 is available in two performance grades: Grade Temperature Range AD698AP – +85 C AD698SQ – +125 C REV. B Information furnished by Analog Devices is believed to be accurate and reliable ...
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... AD698AP Min Typ Max Unit R2 V 0.4 1. 500 ppm of FS 0.1 1 100 ppm 0. ppm 100 ppm/dB 50 300 ppm/V 15 100 ppm/V 25 100 ...
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... Storage Temperature Range P Package . . . . . . . . . . . . . . . . . . . . . . . . . – +150 C Q Package . . . . . . . . . . . . . . . . . . . . . . . . – +150 C Operating Temperature Range AD698SQ . . . . . . . . . . . . . . . . . . . . . . . . – +125 C AD698AP . . . . . . . . . . . . . . . . . . . . . . . . . – +85 C Lead Temperature Range (Soldering 60 sec +300 C Power Dissipation Derates above + Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 mW Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 mW/ C THERMAL CHARACTERISTICS JC JA ...
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AD698 Typical Characteristics (at +25 C and V 240 200 160 GAIN PSRR 15–18V 120 80 40 GAIN PSRR 12–15V 20 OFFSET PSRR 12–15V 0 OFFSET PSRR 15–18V –20 –60 –40 – TEMPERATURE – C Figure ...
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THEORY OF OPERATION A block diagram of the AD698 along with an LVDT (linear variable differential transformer) connected to its input is shown in Figure 5 below. The LVDT is an electromechanical trans- ducer—its input is the mechanical displacement of ...
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AD698 CONNECTING THE AD698 The AD698 can easily be connected for dual or single supply operation as shown in Figures 7, 8 and 13. The following gen- eral design procedures demonstrate how external component values are selected and can be ...
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Multiply the primary excitation voltage by the VTR to get the expected secondary voltage at mechanical full scale. For example, for an LVDT with a sensitivity of 2.4 mV/V/mil and a full scale of 0.1 inch, the VTR = 0.0024 ...
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AD698 Note that V should be chosen so that R3 cannot have negative OS value . Figure 12 shows the desired response. V (VOLTS) OUT +10 +5 +0.1d (INCHES) –0.1 Figure 12 V–10 V Full Scale) vs. Displacement ...
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R2 = 81k – 10kHz EXC –70 0 0.033µF –60 –120 –180 0.1µF –240 R2 = 81k –300 f = 10kHz EXC –360 –420 0 100 1k FREQUENCY – Hz ...
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AD698 Determining LVDT Sensitivity LVDT sensitivity can be determined by measuring the LVDT secondary voltages as a function of primary drive and core posi- tion, and performing a simple computation. Energize the LVDT at its recommended primary drive level, V ...
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OUT Solving for 400 and setting R OUT [400 – 19. Choose an oscillator amplitude that is in the range ...
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AD698 0.005 (0.13) MIN PIN 1 0.200 (5.08) MAX 0.200 (5.08) 0.125 (3.18) 0.023 (0.58) 0.014 (0.36) 0.048 (1.21) 0.042 (1.07) OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 24-Pin Cerdip (Wide) 0.098 (2.49) MAX 24 13 0.610 (15.5) 0.520 ...