LMC8101TP Datasheet, PDF (16/19 Pages) National Semiconductor (TI) – Rail-to-Rail Input and Output, 2.7V Op Amp in micro SMD package with Shutdown

Application Notes (Continued)
LOWER THD
When connected to heavier loads, the LMC8101 has lower
THD compared to the LMC7101. For example, with 5V sup-
ply at 10KHz and 2Vpp swing (Av = −2), the LMC8101 THD
(0.2%) is 60% less than the LMC7101’s. The LMC8101 THD
can be kept below 0.1% with 3Vpp at the output for up to
10KHz (refer to the Typical Characteristics Plots).
IMPROVING THE CAP LOAD DRIVE CAPABILITY
This can be accomplished in several ways:
• Output resistive loading increase:
The Phase Margin increases with increasing load (refer to
the Typical Characteristics Plots). When driving capacitive
loads, stability can generally be improved by allowing some
output current to flow through a load. For example, the cap
load drive capability can be increased from 8200pF to
16000pF if the output load is increased from 5kΩ to 600Ω
(A_V = +10, 25% overshoot limit, 10V supply).
Ordering Information
• Isolation resistor between output and cap load:
This resistor will isolate the feedback path (where excessive
phase shift due to output capacitance can cause instability)
from the capacitive load. With a 10V supply, a 100Ω isolation
resistor allows unlimited capacitive load without oscillation
compared to only 300pF without this resistor (A_V = +1).
• Higher supply voltage:
Operating the LMC8101 at higher supply voltages allows
higher cap load tolerance. At 10V, the LMC8101’s low supply
voltage cap load limit of 300pF improves to about 600pF (A_V
= +1).
• Closed loop gain increase:
As with all Op Amps, the capacitive load tolerance of the
LMC8101 increases with increasing closed loop gain. In
applications where the load is mostly capacitive and the
resistive loading is light, stability increases when the
LMC8101 is operated at a closed loop gain larger than +1.
Package
8-Bump micro SMD
Leaded
8-Bump micro SMD
Lead Free
8-Pin MSOP
Part Number
LMC8101BP
LMC8101BPX
LMC8101TP
LMC8101TPX
LMC8101MM
LMC8101MMX
Package Marking
A
2
A
08
A11
Transport Media
250 Units Tape and Reel
3k Units Tape and Reel
250 Units Tape and Reel
3k Units Tape and Reel
1k Units Tape and Reel
3.5k Units Tape and Reel
NSC Drawing
BPA08FFB
TPA08FFA
MUA08A
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