STM32G474 Buffered vs Unbuffered DAC

[CE2050]

I am using the STM32G474 in STM32CubeIDE with the built-in CubeMx environment. MX_DAC1_Init() to setup the DAC1_Ch1. Internal VREF+ is 2.9V. When it is buffered DAC, I get output very close to 2.9V at max(4095). However if i switch to unbuffered mode, the output is only 1.4+V(about half of 2.9V) at max setting of 4095. There was no mention in the reference manual RM0440 about the change in gain for buffered or unbuffered DAC. Is this normal?

[TDK · Accepted solution]

I’m in buffered mode, the output is higher impedance so it can be pulled down if something is connected externally. The gain is the same.