Datasheet

OPA27, OPA37
11
SBOS135C
www.ti.com
FIGURE 11. Low Frequency Noise Comparison.
FIGURE 10. NAB Tape Head Preamplifier.
FIGURE 9. High Slew Rate Unity-Gain Inverting Amplifier.
OPA37
Output
Input
1kΩ
1kΩ
2
3
6
500pF
250Ω
OPA37
Output
316kΩ
4.99kΩ
G ≈ 50dB at 1kHz.
Metal film resistors.
Film capacitors.
R
L
and C
L
per head
manufacturer’s
recommendations.
100Ω
2
3
6
0.01µF
1µF
20kΩ
R
L
Magnetic Tape Head
C
L
10k
Ω
0.5µV
0.5µV
0.5µV
0.5µV
5µV
A. 741 noise with circuit well-shielded from air
currents and RFI. (Note scale change.)
B. OP-07AH with circuit well-shielded from air
currents and RFI.
C. OPA27AJ with circuit well-shielded from air
currents and RFI. (Represents ultimate
OPA27 performance potential.)
D. OPA27 with circuit unshielded and exposed
to normal lab bench-top air currents.
(External thermoelectric potentials far
exceed OPA27 noise.)
E. OPA27 with heat sink and shield which
protects input leads from air currents.
Conditions same as (D).
Offset
G =1k
10Hz Low-
Pass Filter
Chart
Recorder
10mV/mm
5mm/s
DUT
Total Gain = 10
6
10
Ω