LMC6484AIMX Datasheet, PDF (19/24 Pages) Texas Instruments – LMC6484 CMOS Quad Rail-to-Rail Input and Output Operational Amplifier

Typical Single-Supply Applications (Continued)
DS011714-37
FIGURE 23. Low Voltage Peak Detector with Rail-to-Rail Peak Capture Range
In Figure 23 dielectric absorption and leakage is minimized by using a polystyrene or polyethylene hold capacitor. The droop rate
is primarily determined by the value of C_H and diode leakage current. The ultra-low input current of the LMC6484 has a negligible
effect on droop.
FIGURE 24. Rail-to-Rail Sample and Hold
DS011714-38
The LMC6484’s high CMRR (85 dB) allows excellent accuracy throughout the circuit’s rail-to-rail dynamic capture range.
DS011714-27
FIGURE 25. Rail-to-Rail Single Supply Low Pass Filter
The low pass filter circuit in Figure 25 can be used as an anti-aliasing filter with the same voltage supply as the A/D converter.
Filter designs can also take advantage of the LMC6484 ultra-low input current. The ultra-low input current yields negligible offset
error even when large value resistors are used. This in turn allows the use of smaller valued capacitors which take less board
space and cost less.
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