SBASB59 July 2025 AMC0330S
PRODMIX
The reference input has an internal, 90kΩ impedance connected to GND2. Consider this impedance when driving the REFIN pin from a high-impedance source. Connect a 100nF capacitor from REFIN to GND2 to filter out high-frequency noise at the reference input. Figure 8-3 shows different options for connecting the REFIN pin.
In the first example, REFIN is shorted to GND2 and the resulting reference voltage is 0V. In the second example, VREFIN is derived from VDD2 through a resistive divider. In the third example, an external voltage source drives the reference input pin.