TLE2682 Datasheet, PDF (41/49 Pages) Texas Instruments – HIGH-SPEED JFET-INPUT DUAL OPERATIONAL AMPLIFIER WITH SWITCHED-CAPACITOR VOLTAGE CONVERTER

TLE2682
HIGHĆSPEED JFETĆINPUT DUAL OPERATIONAL AMPLIFIER
WITH SWITCHEDĆCAPACITOR VOLTAGE CONVERTER
SLOS127 − JUNE 1993
APPLICATION INFORMATION
RIPPLE AND SWITCHING NOISE
AT DOUBLER OUTPUT
vs
TIME
40
VCC+ = 5 V
30
IL = 25 mA
CIN = 10 µF
COUT = 100 µF
20 Without Filter
10
0
− 10
RIPPLE AND SWITCHING NOISE
AT DOUBLER OUTPUT
vs
TIME
40
VCC+ = 5 V
30
IL = 25 mA
CIN = 10 µF
COUT = 100 µF
20
10
0
− 10
− 20
− 30
− 40
0
10 20 30 40 50 60 70 80 90 100
t − Time − µs
Figure 97
− 20
Filter:
− 30
LF = 50 µH
CF = 220 µF
See Figure 78
− 40
0 10 20 30 40 50 60 70 80 90 100
t − Time − µs
Figure 98
As with the inverter configuration, when the operational amplifiers are supplied using the voltage converter block,
switching noise are coupled into the signal path through ground. Using the shutdown pin allows precision measurement
of the output signal by an ADC by temporarily disabling the switching mechanism. Figure 99 and Figure 100 show
the decay and charge times at the doubler output with the amplifier connected as shown.
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