MCP6002T-I/P Microchip Technology, MCP6002T-I/P Datasheet - Page 9

• Manufacturer Part Number: MCP6002T-I/P
• Description: Operational Amplifier, Dual channel, V, DIP, 8-Pin
• Manufacturer: Microchip Technology

3.5.3
The MCP6002 has high input impedance, rail-to-rail
input and output, and low input bias current, which
makes this device suitable for a peak detector applica-
tion. Figure 3-7 shows a peak detector circuit with
Clear and Sample switches. The peak detection cycle
uses a clock (CLK), as shown in Figure 3-7.
At the rising edge of CLK, Sample Switch closes to
begin sampling. The peak voltage stored on C
pled to C
end of the sample time (falling edge of Sample Signal),
Clear Signal goes high and closes the Clear Switch.
When the Clear Switch closes, C
for a time defined by t
(falling edge of Clear Signal), op amp A begins to store
the peak value of V
t
FIGURE 3-7:
and Sample CMOS Analog Switches.
DETECT
V
2002 Microchip Technology Inc.
IN
MCP6002
–
+
.
+
MCP6002
–
2
Sample Signal
for a sample time defined by t
PEAK DETECTOR
Clear Signal
B
A
SAMPLE
SWITCH
CLK
CLEAR
IN
D
Peak Detector with Clear
on C
t
SAMP
. At the end of the clear time
t
CLEAR
1
C
2
t
for a time defined by
DETECT
1
C
depletes through R
1
–
MCP6002
+
SWITCH
CLEAR
SAMP
R
C
1
. At the
is sam-
V
OUT
3.5.4
This general purpose amplifier (MCP6002) fits well in a
relaxation oscillator circuit, as shown in Figure 3-8. The
oscillation frequency is set by R and C. The R
resistors are used to set the high and low switching
voltages, as shown in the timing diagram of Figure 3-8.
FIGURE 3-8:
3.5.5
Figure 3-9 shows the MCP6002 op amp used as a tran-
simpedance amplifier in a photo detector circuit. The
photo detector looks like a capacitive current source.
The resistor, R
voltage, V
and produces a low pass response.
FIGURE 3-9:
for an Optical Detector.
C
R
3V
V
1
OH
V
V
OH
= R
Detector
OH
OL
/4
OUT
/4
Photo
2
V
V
RELAXATION OSCILLATOR
R
OPTICAL DETECTOR AMPLIFIER
IN-
IN+
2
. The capacitor, C
1
C
, converts the input signal to the output
2
V
DD
–
+
MCP6002
/2
Relaxation Oscillator.
Transimpedance Amplifier
V
DD
Time
R
R
1
/2
V
MCP6002
DD
R
C
1
1
, stabilizes this circuit
1
MCP6002
DS21733A-page 9
V
V
IN+
V
IN-
V
OUT
V
1
OUT
OUT
and R
2