AD743 Analog Devices, AD743 Datasheet
AD743
Specifications of AD743
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AD743 Summary of contents
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... The combination of low voltage and low current noise make the AD743 ideal for charge sensitive applications such as accelerometers and hydrophones. 3. The low input offset voltage and low noise level of the AD743 provide >140 dB dynamic range. 4. The typical 10 kHz noise level of 2.9 nV/√Hz permits a three op amp instrumentation amplifier, using three AD743s built which exhibits less than 4.2 nV/√ ...
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... Defined as voltage between inputs, such that neither exceeds ± from common The AD743 does not exhibit an output phase reversal when the negative common-mode limit is exceeded. All min and max specifications are guaranteed. Specifications subject to change without notice and 15 V dc, unless otherwise noted ...
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... Output Short Circuit Duration . . . . . . . . . . . . . . . . Indefinite Differential Input Voltage . . . . . . . . . . . . . . . . . . +V Storage Temperature Range ( –65°C to +125°C Operating Temperature Range AD743J . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C Lead Temperature Range (Soldering 60 sec 300°C NOTES 1 Stresses above those listed under Absolute Maximum Ratings may cause perma- nent damage to the device. This is a stress rating only ...
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... AD743–Typical Performance Characteristics (@ 10k LOAD – SUPPLY VOLTAGE ( V) TPC 1. Input Voltage Swing vs. Supply Voltage SUPPLY VOLTAGE ( V) TPC 4. Quiescent Current vs. Supply Voltage 300 200 100 0 –12 –9 –6 – ...
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... Frequency 100 CLOSED-LOOP GAIN = CLOSED-LOOP GAIN = 10 0 100 1k 10k 100k 1M 10M FREQUENCY (Hz) TPC 17. Input Voltage Noise Spectral Density –5– AD743 150 140 130 120 100 SUPPLY VOLTAGE ( V) TPC 12. Open-Loop Gain vs Ω Supply Voltage, R LOAD ...
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... TPC 25. Unity-Gain Inverter Large Signal Pulse Response TPC 26. Unity-Gain Inverter Small Signal Pulse Response –6– TPC 23. Unity-Gain Follower Small Signal Pulse Response 100pF 0 AD743 100pF 4 – SQUARE WAVE INPUT TPC 24. Unity-Gain Inverter OUT REV. E ...
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... RESISTOR ( ) to compute the Johnson noise of a resistor, expressed as a current, one can see that the current noise of the AD743 is equivalent to that of a 3.45 At high frequencies, the current noise of a FET increases pro- portionately to frequency. This noise is due to the “real” part of 1M 10M the gate input impedance, which decreases with frequency ...
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... Figures 4 and 5 show two ways to buffer and amplify the output of a charge output transducer. Both require using an amplifier that has a very high input impedance, such as the AD743. Figure 4 shows a model of a charge amplifier circuit. Here, amplifica- tion depends on the principle of conservation of charge at the ...
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... This graph can be used to JA predict bias current after has been computed. Again, bias cur- JA rent will double for every 10°C. The designer using the AD743 in chip form (Figure 11) must also be concerned with both and , since can be affected by the type of die mount ...
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... Precision accelerometers are typically cali- brated for a charge output (pC/g).* Figures 14a and 14b show two ways in which to configure the AD743 as a low noise charge amplifier for use with a wide variety of piezoelectric accelerom- eters. The input sensitivity of these circuits will be determined by the value of capacitor C1 and is equal to ∆ ...
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... BALANCING SOURCE IMPEDANCES As mentioned previously good practice to balance the source impedances (both resistive and reactive) as seen by the inputs of the AD743. Balancing the resistive components will optimize dc performance over temperature because balancing will mitigate the effects of any bias current errors. Balancing input capacitance will minimize ac response errors due to the amplifier’ ...
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... Changes to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Updated OUTLINE DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2/02—Data Sheet changed from REV REV. D. Edits to PRODUCT DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Edits to CONNECTION DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Deleted AD7435 column from SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Edits to ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Edits to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Deleted METALLIZATION PHOTOGRAPH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Edits to REDUCE POWER SUPPLY OPERATION FOR LOWER I Deleted 8-Pin CERDIP (Q) package drawing ...