SLASF96 April 2024 AFE20408
PRODUCTION DATA
In the AFE20408 mixed DAC range mode, DAC group A is set to a negative-voltage output range (–10V to 0V) and DAC group B is set to a positive-voltage output range (0V to 10V). DAC group B cannot be set to a negative-voltage output range if DAC group A is set to a positive-voltage output range.
The VCC pin of DAC group B must be connected to a positive supply voltage. Typically, the positive voltage at the VCC pin is dictated by the desired positive-voltage output range, but this configuration is not required. In the case where the VCC supply voltage for the positive-voltage output range group is less than the positive-voltage full-scale-range configuration, the maximum DAC voltage is limited to VCC. The VSS pin of DAC group B must be connected to GND.
The VSS pin of DAC group A must be connected to a negative supply voltage. Typically, the negative voltage at the VSS pin is dictated by the desired negative-voltage output range, but this configuration is not required. In the case where the VSS supply voltage for the negative output range group is less than the negative full-scale range configuration, the minimum DAC voltage is limited to VSS. The VCC pin of DAC group A must be connected to GND. Table 6-8 lists the typical configurations for this mode.
PIN | TEST CONDITIONS | TYPICAL CONNECTION |
---|---|---|
VDD | 4.5V to 5.5V | |
VIO | VIO ≤ VDD | 1.65V to 5.5V |
VCCA | GND | |
VCCB | VSS ≤ VDACB ≤ VCC | 3V ≤ VCC ≤ 11V |
VSSA | VSS ≤ VDACA ≤ VCC | –11V ≤ VSS ≤ –3V |
VSSB | GND | |
Thermal Pad | GND |
The VSS[A,B] pins set the clamp voltage for each DAC group. The clamp voltage depends only on the voltage in the VSS[A,B] pins; therefore, changes to the DAC range registers do not affect the clamp setting. The clamp voltage for DAC group A is equal to VSSA, and the clamp voltage for DAC group B is equal to VSSB.