Typical Applications (Continued)
Low Drift Peak Detector
00564623
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•
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By adding D1 and Rf, VD1=0 during hold mode. Leakage of D2 provided by feedback path through Rf.
Leakage of circuit is essentially Ib (LF155, LF156) plus capacitor leakage of Cp.
Diode D3 clamps VOUT (A1) to VIN−VD3 to improve speed and to limit reverse bias of D2.
1
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Maximum input frequency should be
⁄2πRfCD2 where CD2 is the shunt capacitance of D2.
Non-Inverting Unity Gain Operation for LF157
00564675
Inverting Unity Gain for LF157
00564625
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