SBOSA11A March 2020 – March 2021 OPA2206
The OPA2206 has a super-beta input transistor architecture. In a transistor, the beta value is the ratio between the current flowing into the base and the current flowing from the collector to the emitter. A super-beta transistor is one where the beta value has been increased from several hundred to thousands. In a bipolar amplifier, the input bias current is the current flowing into the base of the input transistor pair, as well as a small leakage current that flows through the ESD diodes. A super-beta input reduces the input bias current of the amplifier. In addition, the super-beta inputs lower the input current noise that is directly related to the input bias current of the device. A comparison between the input bias current of the OPA2277 and the OPA2206 super-beta input bias currents can be seen in Figure 8-6 and Figure 8-7.