SBAS945B February 2022 – December 2024 AMC23C14
PRODUCTION DATA
The AMC23C14 is a dual, isolated window comparator with open-drain outputs. Window comparator 1 is comprised of comparator Cmp0 and Cmp1 and window comparator 2 is comprised of Cmp2 and Cmp3. Cmp0 and Cmp2 compare the input voltage (VIN) against the respective positive thresholds (VIT+) and Cmp1 and Cmp3 compare the input voltage (VIN) against the respective negative thresholds (VIT–). The respective VIT+ and VIT– thresholds are of equal magnitude but opposite signs, therefore both window comparators have windows that are centered around 0V. Window comparator 2 has fixed thresholds of ±300mV. Window comparator 1 has adjustable thresholds from ±20mV to ±300mV through an internally generated 100μA reference current and a single external resistor.
The open-drain outputs are actively pulled low when the input voltage (VIN) is outside the respective comparison window, but are otherwise in a high-impedance state.
When the voltage on the REF pin is greater than VMSEL, the device operates in positive-comparator mode. This mode is particularly useful for monitoring positive voltage supplies. Both negative comparators (Cmp1 and Cmp3) are disabled and only the positive comparators (Cmp0 and Cmp2) are functional. The reference voltage in this mode can be as high as 2.7V.
Galvanic isolation between the high- and low-voltage side of the device is achieved by transmitting the comparator states across a SiO2-based, reinforced capacitive isolation barrier. This isolation barrier supports a high level of magnetic field immunity, as described in the ISO72x Digital Isolator Magnetic-Field Immunity application note. The digital modulation scheme used in the AMC23C14 to transmit data across the isolation barrier, and the isolation barrier characteristics, result in high reliability and common-mode transient immunity.