AD5758 have no negative voltage output

Hi,

AD5758 is an new released chip, and now, I use this chip on my board to generate +/-10V voltage.

The circuit as follow:

I got some issue with this chip, could you helps to take a look this.

1

for the Vsense+ pin,

in page 16 of datasheet, "if remove sensing is not being used, short this pin to VIout via a series 1K RES",

in page 16 of datasheet, "if remove sensing of load is not required, connect +Vsense directly to VIout and connect -Vsense directly to AGND".

So, I am confuse whether I should add 1K resistor between VIout and +Vsense pin, please helps to take a look.

2.

My board now can generate 0-10V voltage successfully, but, it can't generate negative voltage.

the VSS is -15V, I have measured it, looks my register configration for ADC is correct also, I have checked it several time.

But, I wonder why I can't get negative voltage. whether I should connect -Vsense to VIout also rather than AGND.

Or, could you helps to analysis the other reason.

Very thanks.

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