Datasheet

'
A
OL
G
min
f
d
f
1
fu
f
2
f
u
f
GBWP
UNITY-GAIN STABLE OP AMP
DECOMPENSATED OP AMP
1k
100k
100M
-20
20
100
GAIN (dB)
10M
1M
10k
80
40
0
60
FREQUENCY (Hz)
-20
20
100
80
40
0
60
PHASE
(
°
)
1k
100k
100M
-20
20
100
GAIN (dB)
10M
1M
10k
80
40
0
60
FREQUENCY (Hz)
GAIN
PHASE
-20
20
100
80
40
0
60
PHASE
(
°
)
LMV793, LMV794
www.ti.com SNOSAX6D –MARCH 2007–REVISED MARCH 2013
Figure 41. LMV793 A
VOL
vs. Frequency
Figure 42. LMV796 A
VOL
vs. Frequency
Figure 41 shows the much larger 88 MHz bandwidth of the LMV793 as compared to the 17 MHz bandwidth of
the LMV796 shown in Figure 42. The decompensated LMV793 has five times the bandwidth of the LMV796.
What is a Decompensated Op Amp?
The differences between the unity gain stable op amp and the decompensated op amp are shown in Figure 43.
This Bode plot assumes an ideal two pole system. The dominant pole of the decompensated op amp is at a
higher frequency, f
1
, as compared to the unity-gain stable op amp which is at f
d
as shown in Figure 43. This is
done in order to increase the speed capability of the op amp while maintaining the same power dissipation of the
unity gain stable op amp. The LMV793/LMV794 have a dominant pole at 1.6 kHz. The unity gain stable
LMV796/LMV797 have their dominant pole at 300 Hz.
Figure 43. Open Loop Gain for Unity-Gain Stable Op Amp and Decompensated Op Amp
Copyright © 2007–2013, Texas Instruments Incorporated Submit Documentation Feedback 13
Product Folder Links: LMV793 LMV794