Datasheet

INA330
10
SBOS260
www.ti.com
FIGURE 9. Required 1.6kHz (or lower) Filtering.
FILTERING
Subsequent stages will frequently provide adequate filtering
for the INA330. However, filtering can be adjusted through
selection of R
G
C
FILTER
, and by adding a filter at V
O
for the
desired trade-off of noise and bandwidth. Adjustment of
these components will result in more or less ripple due to
auto-correction circuitry noise and will also affect broadband
noise.
It is generally desirable to keep any resistor added at V
O
(see
R
O
in Figure 9) relatively low to avoid DC gain error created
by the subsequent stage loading. This may result in relatively
high values for the filter capacitor at V
O
to produce the
desired filter response. The impedance of this filter can be
scaled higher to produce smaller capacitor values if the load
impedance is very high. Electrolytic capacitors are not rec-
ommended for the filters due to dielectric absorption effects.
FIGURE 8. Simple PI Temperature Control Amplifier.
R
G
200kΩ
C
FILTER
500pF
INA330
REF3012
V
ADJ
R
SET
10kΩ
R
THERM
10kΩ
4
0.1µF
V
EXCITE
1.25V
2µF
(1)
10MΩ
(1)
100pF
(1)
2
3
10
1
+5V
95 6
8
7
OPA340
V
REF
2.5V
V
O
Output
to Power Amp
+5V
10MΩ
(1)
NOTE: (1) Time constants
were selected for THORLABS
model TCLM9 Laser Diode
Mount.
Proportional-Integrator
compensation is simpler to
adjust and often provides
adequate thermal transient
response.
8
7
2
3
10
1
R
G
200kΩ
C
FILTER
500pF
C
O
1µF
R
O
100Ω
V
ADJ