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LT8302 Not Workin

Category: Hardware
Product Number: LT8302

Hi Technical Team,

My target application Vin=24 V, Vo=19 V, Io=52.63 mA. Split this 19 V to +15 V and -4 V using zener diodes.

According to LT8302 datasheet procedure, I have chosen a 750313445 transformer which has required inductance and turns ratio. My calulated Rfb=95.8 kohm, output cap is 47 uF. Rsnub=47ohm, Csnub=0.33 nF.  Connected two zeners of 16V and 3V after 19V rail (in order to split the voltages).

Problem 1: Leakage ringing is suppressed before 200 ns (as suggested in datasheet) as I see in the oscilloscope. The problem I am facing is, the output voltage is 18.2 V only. I adjusted the Rfb as shown in datasheet, but nothing has changed. 

Problem 2: The output voltage still reduces as I increase the load. 

Where am I missing? Kindly help.