ZAMC4100 Datasheet, PDF (140/155 Pages) Integrated Device Technology – Actuator and Motor Controller

ZAMC4100 Datasheet
5 ZAMC4100 Protection and Diagnostic Features
This section is a summary description of all protection and diagnostic features available in the ZAMC4100. The
description is structured similarly to the way the diagnostics are handled:
event à detection à capturing à reaction
5.1. Full-Time Diagnostic and Protection Features
It includes features that might always be present whenever the system is powered and do not interrupt or
influence the normal operation. They are executed in the background automatically and interrupt the normal
operation only if a specific event occurs. Some of these features might be masked by the software and MCU;
others cannot be masked (mainly protection functions).
5.1.1.
Event
Over-Current (OC) Protection
The current through one of the output driver transistors is above the maximum specified value for
the corresponding output.
Detection
Continuous comparison with a fixed reference level with pure analog circuitry; possible measuring
with the ADC in parallel; invoked by the software.
Capturing Captured in the digital SBC.
Reaction
Response in both digital and analog domains:
1) The driver of this transistor automatically limits the current in order to avoid silicon damage.
Important: This reaction is implemented as analog circuitry, and it cannot be masked.
2) An over-current interrupt flag is set in the digital SBC, and the drivers are automatically
disabled.
5.1.2. Over-Load (OVL) Detection using the ADC
Event
The current through one of the output driver transistors is above a certain limit (OVL level) that is
considered as a maximum current allowed for the driven load. The OVL level is always below the
OC level.
Detection
Initiated by the MCU firmware. The measured current by the ADC is compared with the OVL level
in the MCU or with the ADC comparator.
Capturing The event is captured in the MCU.
Reaction
A response should be implemented in the MCU software depending on the application
requirements.
© 2016 Integrated Device Technology, Inc.
140
January 26, 2016