9.1 Output Stage Compensation

The complex load impedances common in power operational amplifier applications can cause output stage instability. For normal operation output compensation circuitry is typically not required. However, if the OPA548 is intended to be driven into current limit, an R/C network may be required. See Figure 38 for an output series R/C compensation (snubber) network which generally provides excellent stability.

A snubber circuit may also enhance stability when driving large capacitive loads (> 1000 pF) or inductive loads (motors, loads separated from the amplifier by long cables). Typically 3 Ω to 10 Ω in series with 0.01 μF to 0.1 μF is adequate. Some variations in circuit value may be required with certain loads.