OPA363 Datasheet, PDF (11/27 Pages) Texas Instruments – 1.8V, 7MHz, 90dB CMRR, SINGLE-SUPPLY, RAIL-TO-RAIL I/O OPERATIONAL AMPLIFIER

ACTIVE FILTERING
Clean 3.3V Supply
49kΩ
Low harmonic distortion and noise specifications plus high
gain and slew rate make the OPA363 and OPA364 optimal
3.3V
candidates for active filtering. Figure 11 shows the OPA2363
configured as a low-distortion, 3rd-order GIC (General Immit-
4kΩ
tance Converter) filter. Figure 12 shows the implementation
OPAx363
OPAx364
V_OUT
of a Sallen-Key, 3-pole, low-pass Bessel filter.
Electret
6kΩ
5kΩ
Microphone
1µF
FIGURE 10. Microphone Preamplifier.
R₁
V_IN
3.92kΩ
R₃
1.33kΩ
2
OPA363 ⁶
3
V_OUT
6
7
1/2
OPA2363 ₅
R₁₁
3.92kΩ
R₁₂
3.92kΩ
C₁₃
1000pF
3
1/2
1
2 ^OPA2363
C₄
1000pF
R₁₄
3.48kΩ
C₁₅
1000pF
FIGURE 11. The OPA2363 as a 3rd-Order, 40kHz, Low-Pass GIC Filter.
220pF
V_IN = 1Vrms
1.8kΩ
19.5kΩ 150kΩ
3.3nF
47pF ^OPA363
V_OUT
FIGURE 12. The OPA363 or OPA364 Configured as a 3-Pole, 20kHz, Sallen-Key Filter.
OPA363, 2363, 364, 2364, 4364
11
SBOS259B
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