OPA111 Datasheet, PDF (10/14 Pages) Burr-Brown (TI) – Low Noise Precision Difet OPERATIONAL AMPLIFIER

–46dBm to
–20dBm
RF Input 1000pF
RFC
100Ω
10kΩ
H-P
HSCH-3486
2
6
OPA111
3
e_O
DC
Output
1MΩ
e_O ≈ 1200mVDC/µW
Video bandwidth: DC to 50kHz
FIGURE 7. Zero-Bias Schottky Diode Square-Law RF
Detector.
500pA
I_IN
Light Rays
X-Rays (Pencil Beam)
R_F
100MΩ
2
6
OPA111
3
e_O = 50mV
e_O = –I_IN R_F
Pin Photodiode
Scintillation Crystal
<1pF to prevent gain peaking.
1000MΩ
H-P 5082-4204
Pin Photodiode
0.01µF
+15V
Guard
0.1µF
2
8
7
6
OPA111
34
1000MΩ
0.1µF
Output
5 x 10⁸V/W
–15V
Circuit must be well shielded.
FIGURE 10. Sensitive Photodiode Amplifier.
Offset voltage =
255µVDC maximum
with no offset adjust.
5.34MΩ* 5.34MΩ*
2
6
OPA111BM
Input
3
1000pF
2.67MΩ*
Output
Q
2kΩ
500pF
500pF
*For 50Hz use:
3.16MΩ and 6.37MΩ
FIGURE 11. 60Hz Reject Filter.
Collimator
X-Ray Tube
FIGURE 8. Computerized Axial Tomography (CAT) Scan-
ner Channel Amplifier.
500Ω
9.5kΩ
Guard
+15V
pH Probe
R ≈ 500MΩ
50mV Output
2
8
OPA111 ^{7 6}
3
4
1VDC
Output
5
1
Offset Trim
100kΩ
–15V
∆Q
100pF
C_{F 100pF}
R_F
10¹⁰Ω
28
6
Output
OPA111
e_O
3
10¹⁰Ω
e_O = –∆Q/C_F
Low frequency cutoff =
1/(2 π R_FC_F) = 0.16Hz
FIGURE 12. Piezoelectric Transducer Charge Amplifier.
In
375.1kΩ
375.1kΩ
187.5kΩ
1µF
1µF
2
8
6
Out
3 ^OPA111
F_C = 0.6Hz
–80dB at 60Hz
FIGURE 9. High Impedance (10¹⁴Ω) Amplifier.
®
OPA111
FIGURE 13. 0.6Hz Second-Order Low-Pass Filter.
10