Neus, I know that there have been others that have used the internal buck-boost to drive external circuitry, but we haven't characterized the device in this way. Looking at the 4-channel version (DAC8775), I have seen at least one case where the device had a hard time starting up at higher temperatures when loaded with the TLV9362. These op-amps, at two for each channel, would cause problems for the buck-boost. When these op-amps were replaced with the OPA2990, I think these problems were removed. For the OPA192, the operating current is higher than the OPA2990, so I'm not sure how different the startup current profile would be from one device to the next. You would also need to consider the bypass capacitors for each op-amp as part of the load. Regardless, this is what you'd need to consider using the internal buck-boost to drive other devices. If you're interested in testing it, I would consider getting a DAC8771EVM and setting it up to power an op-amp. This would be a good test for this application. Joseph Wu
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