Would you please tell me which channel are you using? HSADC0A or HSADC0B

If you connect external signal to PTE3, then you may need to :
void HSADC0_CCB_IRQHandler(void)
{
HSADC_ClearStatusFlags(DEMO_HSADC_BASEADDR, kHSADC_ConverterBEndOfScanFlag);
}
EnableIRQ(HSADC0_CCB_IRQn);
HSADC_EnableInterrupts(DEMO_HSADC_BASEADDR, kHSADC_ConverterBEndOfScanInterruptEnable);
The Conversion complete interrupts and Scan interrupts are different. Please read "41.6 Interrupts" in KV5XP144M240RM.

HSADC_EnableInterrupts can be used to enable Conversion complete interrupts.

HSADC_EnableSampleResultReadyInterrupts is used to enable Scan interrupts.

Best Regards,
Robin
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