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AD8330 Gain Adjustment Output Constant Issue

The use of AD8330 to the front stage for gain compensation, single-ended input and single-ended output, 5V power supply, please ask the AD8330 output voltage range is 0-2VMAG Well, pin VMAG suspended, GMAG is 1 Well, the circuit test, VMAG suspended, VDBS is 0.55V, the output of the AD8330 test the value of the voltage has always been 2.5V unchanged, regardless of how the VDS How to change, the output pin 13 (OPHI) value is unchanged, has been 2.5V or so; (2) the input will be directly through the lead into the 4 (INHI) pin DC voltage 1v, then the digital power supply sender will rise to 1.4V or so, the digital power supply output is greater than 1.4V, the display is only stable, I do not know what causes, this time to change the value of the VDBS, from 0 to 5V I want to realise that the output voltage range of AD8330 is 0~3.3V, how to change the circuit design, I follow the information I got from the manual, that is, the voltage value of VMAG is 1.65V, that is, the output voltage range of AD8330 is 0 to 3.3V, and the range of gain control voltage of GVDBS is 0 to 1.5V that is, the gain range is 1 - 316; (4) the current debugging, AD8330 input (INHI) value regardless of how the size of the change, change the value of the gain VMAG (1.56V, 4V , 4.5V), in the change of the gain VDBS, the value of the output leg (OPHI) does not change much, the test has been about 2.5, please ask, how to solve this problem; Circuit design schematic as attached