SBOU268 November 2021 OPA593
The OPA593 DNT (12-pin WSON) package provides separate current limit and thermal shutdown flag functions that indicate when an overcurrent or overtemperature condition occurs. These two functions have pins that are open-drain, active-low outputs, internally referenced to the applied E/D Com pin voltage; E/D Com is shown as EDcom on the EVM board. An LED and series 820-Ω resistor serve as the pulldown load for each status flag pin to the E/D Com pin (EDcom). The OPA593EVM has a separate 3.3-V regulator that is referenced to E/D Com pin (E/D com) and serves as the supply in this circuit.
An LED illuminates when an overcurrent or overtemperature condition is reached. An orange overcurrent LED illuminates when the output current exceeds the limit selected by the jumper shunt connected across one of the JP12 through JP16, 50-mA to 250-mA current-limit selections. The red overtemperature LED activates if the OPA593 junction temperature (TJ) is greater than 150°C, but turns off after the device cools to 130°C. The OPA593EVM has an extensive heat-sinking area; therefore, triggering the overtemperature LED may be difficult. The status flag pins can be monitored externally using the TP9 current-limit test point and TP8 thermal-limit test point.