The TPS4141-Q1 can also dynamically switch between uni-directional and bi-directional voltage sensing. REF connects to an external precision voltage reference, identical to the bi-directional configuration.

DIV0 and DIV1 pins are trinary inputs in that the pins can detect a logic low or high, as well as a Hi-Z condition present on the respective pins. The states of the DIV0 and DIV1 pins not only select the divide ratio (DIV), but also configure the device for bi-directional or uni-directional voltage sensing. When in bi-directional operation, use the external reference voltage present on the REF pin and the TPS4141-Q1 measures both positive and negative voltages present on HV referenced to HVGND, for example, from –1200V to 1200V. The voltage output of AOUT swings above and below the voltage present on the REF pin. When in uni-directional operation, the external reference voltage is bypassed internal to the device and HVGND is used as the reference and the TPS4141-Q1 can measure only positive voltages present on HV referenced to HVGND, for example, 0V to 1200V. The voltage output of AOUT always is positive referenced to HVGND. Figure 6-3 and Figure 6-4 show these cases.

The divider ratio selected by DIV0 and DIV1, and reference voltage applied to REF determine the measurement accuracy of the range of voltages. See High Voltage Input Range for supported ranges. Normally, the external reference voltage is selected to allow for symmetry of allowable ranges that can be supported for positive and negative input voltages, however this is not required.