I use LP2996 as VTT in DDR-SDRAM.
VIN and SD are connected. The output capacitor capacity is 47uF.
When input voltage is ramped up very slowly in this state, a inrush current flows.
Please see attached file. CH1:VIN, CH2:VTT, CH3:VREF, CH4:Iin
I guess a inrush current to be flow inside the IC because the output current isn't increased.
2.5V is being generated by LM43601, so an over-current is detected by this Inrush current.
When toggling SD pin to High from Low, this inrush current isn't flow.
.
I have two questions.
1. When VIN is below the recommendation operation voltage(<2.2V), does this phenomenon occur?
2. Isn't there a UVLO function in LP2996?