OP-AMPS: PART IIActive Filters in Real-World
Applications
Entanglement and Decoherence in a Trapped-Ion Quantum Register by David Kielpinski, UC-Boulder, PhD Thesis, 2001
Heart Monitor
Ella Clare, March 24, 2013 2 lb 8 oz
Non-inverting active filters
Non-inverting LPF (Boost)
10-1
100
101
102
103
104
105
106
-60
-50
-40
-30
-20
-10
0
log10
f (Hz)
(f)
deg
rees
Non-inverting LPF
10-1
100
101
102
103
104
105
106
0
5
10
15
20
25
30
log10
(f)
G(f
) dB
Non-inverting LPF
Cutoff freq Hz
Non-inverting (HPF)
10-1
100
101
102
103
104
105
106
0
10
20
30
40
50
60
log10
f (Hz)
(f)
deg
rees
Non-inverting HPF
10-1
100
101
102
103
104
105
106
0
5
10
15
20
25
30
log10
f (Hz)G
(f) d
B
Non-inverting HPF
Cutoff freq
TAKE THAT OLD RECORD OFF THE
SHELFRIAA Pre-amp
Pop quiz: what 2 things do hipsters love?
Pickup Line: Magnetic cartridge
Cutting vinyl: The issue with playback
Bass freqs: Large groove amplitude: lower spatial density of information
Treble freqs: small groove amplitude: potentially noisy (low SNR)
Mastering an LP
RECORDING: EMPHASIZE TREBLE, DE-EMPHASIZE BASS PLAYBACK: RE-EQUALIZE
101
102
103
104
105
-20
-15
-10
-5
0
5
10
15
20
log f (Hz)
G(f
) dB
RIAA Recording Emphasis Curve
101
102
103
104
105
-20
-15
-10
-5
0
5
10
15
20
log f (Hz)
G(f
) dB
RIAA Re-equalization
Recording
Playback
RIAA phono preamp
Cartridge interface Re-Equalization BPF Non-inverting amp
Circuit from: National Semiconductor Note 346. High-performance audio applications
The Performance
GAIN PHASE
10-1
100
101
102
103
104
105
-100
-80
-60
-40
-20
0
20
40
60
80
100
log f Hz
(f)
10-1
100
101
102
103
104
105
0
10
20
30
40
50
60
log f (Hz)
G(f
) dB
RIAA Preamp
Blue line = circuit performanceRed dots = RIAA specified gains at 20 test frequencies
deg.