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1.In each of the following cases, the IC2 is damaged;about 5% percent；VIN:9V, Vout:=15v/-15V,100mA
a. when the power was turned on(Test no load or with load all have damaged);Use a multimeter to test: there is no difference between damaged IC pins and normal IC;
b. when the power is turn on,VIN=9V,Iout=100mA, after a later,The tps54240 is about 4-5% percent of the damage occurred,I test with a multimeter,pin2 and pin11 is short;
c. when I test Short circuit protection,,-15V output Short circuit protection is OK,but the +15V output Short circuit protection is not OK,and +15V output Short will damaged IC2,Use a multimeter to test: there is no difference between damaged IC pins and normal IC? why +15V output No short circuit protection?
d. PIN10 TO -15V waveform as below; and VIN TO -15V waveform is not have any spikes;
2. I find the datasheet in 7.3.14, when the Frequency rising,the VIN is voltage falling,so I use the WEBENCH® Designer ,the result Switching frequency<700K,then I use 600K frequency,and test the result is about 4% percent of the damage occurred,I test with a multimeter,pin2 and pin11 is not short,but the IC can not work!
3. how to Solve this problem?
