Can you confirm what value is loaded in the Chip_ID register 0x00? We do not see 0xD7780 as indicated in the datasheet. We thought maybe D7780 meant decimal 7780, but even that doesn’t explain the value we are seeing. If we read other registers, we see the expected default values so we believe we are handling the SPI transactions correctly. Was the device ID changed when production shifted from Hittite to Analog? It’s not very urgent but as many people use the device ID to check the SPI interface is working, having the correct number in the datasheet is important.