Reinforced isolated amplifiers are commonly offered in SOIC packages with less than 9 mm of clearance and creepage specification. Automotive systems supporting working voltages greater than 850 V, designed for altitudes greater than 2000 m or for environments with pollution degree 2 or higher, may require clearance and creepage distances greater than 9 mm. Examples are OBC, DC/DC converters, and traction inverters for 800-V automotive battery systems that support DC-bus voltages up to 1000 V.

The AMC1411-Q1 comes in a SOIC package with greater than 15.7 mm of creepage distance and is specifically designed for use in high-voltage systems that require accurate voltage monitoring and reinforced isolation between high-voltage and low-voltage parts of the system.

Figure 8-1 shows an OBC that uses the AMC1411-Q1 to monitor the DC-bus voltage that can be as high as 1000 V. The DC-bus voltage is divided down to an approximate 2-V level across the bottom resistor (RSNS) of a high-impedance resistive divider that is sensed by the AMC1411-Q1. The output of the AMC1411-Q1 is a differential analog output voltage of the same value as the input voltage but is galvanically isolated from the high-side by a reinforced isolation barrier.

The wide creepage and clearance, high isolation voltage rating, and high common-mode transient immunity (CMTI) of the AMC1411-Q1 ensure reliable and accurate operation in harsh and high-noise environments.