SBAS945A February 2022 – July 2022 AMC23C14
PRODUCTION DATA
Keep the connection between the low-side of the sense resistor and the GND1 pin of the AMC23C14 short and low impedance. Any voltage drop in the ground line adds error to the voltage sensed at the input of the comparator and leads to inaccuracies in the trip thresholds.
For best common-mode transient immunity, place the filter capacitor C5 as closely to the REF pin as possible as illustrated in Figure 8-10. Use a low value pullup resistor (<10 kΩ) on the open-drain output, as explained in the Section 7.3.4 section, to minimize the effect of capacitive coupling on the open-drain signal line during a common-mode transient event.
Do not exceed the 300-mV VREF limit specified in the Section 6.3 table for bidirectional current-sensing applications. Do not operate the device with the REF pin biased close to the VMSEL threshold (450-mV to 600-mV range) to avoid dynamic switching of the Cmp0 hysteresis as explained in the Section 7.3.2 section.
The AMC23C14 provides a limited 200-μs blanking time (tHS,BLK) to allow the reference voltage (VREF) to settle during start up. For many applications, the reference voltage takes longer to settle than the 200-μs blanking time and the output of the comparator can possibly glitch during system start up as described in Figure 7-2. Consider the reference voltage settling time in the overall system start-up design.