ZNRG2061 Evaluation Kit User Manual
© 2017 Integrated Device Technology, Inc.
8
March 29, 2017
2.
Usage Guide
Refer to the ZNRG2061 Software User Manual for full details for using the software.
2.1
Monitoring Output Signals
The outputs signals ADF and AFS are used by the system to monitor the status of the arc detection. They are available on the Evaluation
Board (see Table 1 for the pin locations). Figure 5 shows the possible states for the output signals.
Figure 5. AFD and AFS State Diagram
2.1.1
AFD – Arc Fault Detector
The AFD pin is static, and it can be used to control a DC break switch directly in the event of detecting an arc. If an arc is detected, the AFD
output level goes HIGH.
If the ZNRG2061’s built-in self-test (BIST) detects a malfunction, the AFD pin will be set HIGH. In the event of a malfunction, the ZNRG2061
might attempt to recover automatically. If the final recovery attempt is not successful, the AFD pin will be set HIGH.
If set, the AFD pin is permanently latched HIGH, and the ZNRG2061 will not reset the output by itself. Only a power off/on cycle or a GUI
command can reset this pin.
The red AFD LED indicator on the Evaluation Board (see Figure 2) is on if the AFD pin is set HIGH; otherwise it is not on.
2.1.2
AFS – Arc Feature Signal
The AFS pin is dynamic, and it outputs a signal similar to pulse width modulation (PWM). The information on this pin is defined by the width of
the positive pulse width in milliseconds.
This pin can be used for the following purposes:
The AFS pin can serve as secondary validation pin. This can be implemented on a system level. The AFS pin is designed to be
complementary (dynamic vs. static) to the AFD pin, so that there is an opportunity for detecting a complete component failure.
The AFS output can be used to indicate an error condition as part of its normal functions. It will stop its PWM-like pulses if a malfunction is
detected. A small external circuit (for example, a watchdog circuit) can be used to display the state on the LED.
Example: In the unlikely case of a ZNRG2061 malfunction during an arcing event, the AFD might not be triggered. In this case, the AFS pin
will remain static HIGH or LOW (PWM 0% or 100%), thus indicating the error.
The AFS pin is connected to the white AFS LED indicator which reflects the PWM signal.
