2.3 Current Detection Circuit
1. Circuit composition
ACS720 current chip is used for sampling, the chip outputs 1.5V bias voltage with zero
current and provides a 1.5V REF. The sampling signal is calculated by the operational
amplifier and sent to the control board.
In addition, the internal circuit of the chip detects a delay of 4us, which is a large delay
for the overcurrent protection function, so the internal overcurrent protection function is
introduced.
The ACS720 has a user-configurable double-fault function, with fast and slow fault
outputs for short-circuit and overcurrent fault detection. Using the fast protection pins
VOC_F and FAULT_F/, the device sends out a low FAULT signal within 1.5us when the
AC310 Universal AC Drive Service Manual
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