The STPS60170CT is a 170 V, 30 A per diode Schottky rectifier array from STMicroelectronics, configured as a common-cathode pair in a through-hole TO-220-3 package. It targets high-efficiency power conversion stages — boost PFC, output rectification in switched-mode supplies, and freewheeling diodes in motor drives — where the Schottky barrier's low forward drop and fast recovery (< 500 ns) cut switching losses versus a standard ultrafast diode.
Forward voltage and junction temperature — the thermal budget drivers
At 30 A forward current the typical forward voltage is 940 mV — this is the conduction loss floor per diode. With both diodes conducting the total dissipation at 60 A combined is 56.4 W, which must be sunk through the TO-220 tab. The maximum junction temperature is 175 °C, so the heatsink must keep Tj below that under worst-case ambient and load. Reverse leakage at rated 170 V is 35 µA — negligible at room temperature but it rises exponentially with junction temperature. In a high-duty-cycle boost stage running at 125 °C Tj, the leakage contribution to the thermal budget can become significant; derate the output current if the ambient is above 85 °C.