Nithin, I'd asked this before, but what it the model of the transformer you are using? I'm still not sure what the problem is, but can you set the device to enable the buck-boost positive arm and disable the negative arm? This is the 01 setting of PNSEL[1:0] in the Configuration Buck-Boost Register. You would then set the DAC to current output mode, but set the code to 0x0000 with maybe a 1kΩ load. Then go back to the Configuration Buck-Boost Register and set the PCLMP to values of 0x0000 to 0x1111. You'll want to measure the VPOS_IN_A voltage at the same time to see that it rises. The values given in the table are coarse measurements, and you may be off by 0.5V to 1V. Regardless, I want to see that the voltage goes up to the expected 32V without the load. There may be a high-side clamp that limits you to 26V instead. The HSCLMP register in the User Alarm Code sets this, and can be set back to the higher clamp setting. This basically checks that the VPOS_IN_A can go up with an unloaded condition. In previous tests we did have some sort of load. If the output does not go all the way up to about 32V, then I really think you have something external to the device on your board at the output that is clamping the output. Joseph Wu
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