Typical Applications (Continued)
High Accuracy Sample and Hold
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By closing the loop through A2, the VOUT accuracy will be determined uniquely by A1.
No VOS adjust required for A2.
TA can be estimated by same considerations as previously but, because of the added
propagation delay in the feedback loop (A2) the overshoot is not negligible.
Overall system slower than fast sample and hold
R1, CC: additional compensation
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Use LF156 for
j
j
Fast settling time
Low VOS
High Q Band Pass Filter
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By adding positive feedback (R2)
Q increases to 40
fBP = 100 kHz
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Clean layout recommended
Response to a 1Vp-p tone burst: 300µs
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