OPA336 Datasheet, PDF (8/8 Pages) Burr-Brown (TI) – SINGLE-SUPPLY, MicroPOWER CMOS OPERATIONAL AMPLIFIERS MicroAmplifier ™ Series

For example, with R_L = 25kΩ, OPA336 series op amps
perform well with capacitive loads in excess of 1000pF
(Figure 4). Without R_S, capacitive load drive is typically
350pF for these conditions (see Figure 5).
Alternatively, the resistor may be connected in series with
the output outside of the feedback loop. However, if there is
a resistive load parallel to the capacitive load, it and the
series resistor create a voltage divider. This introduces a DC
error at the output. However, this error may be insignificant.
For instance, with R_L = 100kΩ and R_S = 100Ω, there is only
about a 0.1% error at the output.
Figure 5 shows the recommended operating regions for the
OPA336. Decreasing the load resistance generally improves
capacitive load drive. Figure 5 also illustrates how stability
differs depending on where the resistive load is connected.
With G = +1 and R_L = 10kΩ connected to V_S/2, the OPA336
can typically drive 500pF. Connecting the same load to
ground improves capacitive load drive to 1000pF.
V_S = +5V, V_O = V_S/2
10k
Operation Above Selected Gain
Curve Not Recommended
G = +1
R_L to Ground
G = +2
R_L to Ground
1k
G = +1
R_L to V_S/2
100
5
10
100
Resistive Load (kΩ)
FIGURE 5. Stability—Capacitive Load vs Resistive Load.
®
OPA336, 2336, 4336
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