SBAS789B October 2017 – April 2020 AMC1106E05 , AMC1106M05
PRODUCTION DATA.
For lowest system-level cost, the high-side power supply (AVDD) for the AMC1106 is derived from an external capacitive-drop power supply. The Magnetically Immune Transformerless Power Supply for Isolated Shunt Current Measurement reference design and Figure 52 shows a proven solution based on a 6.2-V diode and the TLV70450 5-V low dropout (LDO) regulator. A low equivalent series resistance (ESR) decoupling capacitor of 0.1 µF is recommended for filtering this power-supply path. Place this capacitor (C5 in Figure 52) as close as possible to the AVDD pin of the AMC1106 for best performance.
The floating ground reference (AGND) is derived from the end of the shunt resistor that is also connected to the negative input (AINN) of the device. If a four-pin shunt is used, the device inputs are connected to the inner leads and AGND is connected to one of the outer leads of the shunt.
For decoupling of the digital power supply on the controller side, TI recommends using a 0.1-µF capacitor (C6 in Figure 52) assembled as close to the DVDD pin of the AMC1106 as possible, followed by an additional capacitor in the range of 1 µF to 10 µF.