DG401 Datasheet, PDF (10/10 Pages) Intersil Corporation – Monolithic CMOS Analog Switches

DG401/403/405
Applications (Cont’d)
Peak Detector:
A₃ acting as a comparator provides the logic drive for
operating SW₁. The output of A₂ is fed back to A₃ and
compared to the analog input e_in. If e_in > e_out the output of
A₃ is high keeping SW₁ closed. This allows C₁ to charge
up to the analog input voltage. When e_in goes below e_out A₃
goes negative, turning SW₁ off. The system will therefore
store the most positive analog input experienced.
Reset
–
e_in
+^A1
+_A3
–
SW₂
SW₁
R₁
+_A2
–
e_out
DG401
C₁
Figure 12. Positive Peak Detector
10
Siliconix
S-53748—Rev. E, 05-Jun-97