1. LDO has internal thermal shutdown protection, which says "If power dissipation causes the junction temperature to exceed specified limits the device will go into thermal shutdown".
Tried shorting Vout & gnd. Temp increased to 108°C, but the device didn't go bad. 5V Vout was still coming. Then applied hot air & increased temp to 200°C on the IC package externally & simultaneously shorted output. At around 160°C (Abs Max 150°C), thermal shutdown occurred, but the device still didn't go bad.
From here we can conclude that LDO itself won't go bad in any condition of increased power dissipation. In worst case thermal shutdown will occur & LDO is protected.
2. As my target was to blow up LDO. So shorting o/p & increasing temp didn't help. I then increased voltage to 20V (Abs Max 12V) with shorted o/p & increased temp. LDO went bad. Vout & Vin measured 6 ohm (short).
Conclusion :
LDO was blown up only by increasing I/P Voltage beyond abs max & not by increased power dissipation.
My queries :
1. Thermal shutdown will protect LDO always in excessive power dissipation by LDO. Please confirm.
2. When LDO goes bad, Vout & Vin gets shorted. So whatever is voltage given at i/p, it leaks at o/p. Please confirm.
