LTM4637EV#PBF bulk capacitor

Dear Community,

In our new design we were using LTM4637EV#PBF part to generate 1V vout from 12v input.
This 1V supply is used as FPGA Core voltage and Regulator is kept very close to the FPGA.
As per Regulator datasheet, we placed 2# 470uF bulk cap & 5# 100 uF capacitor at Vout.
And FPGA manufacturer suggested to place 4# 680uF Capacitot at 1V rail near to FPGA.
Since our board is densed and we have a place constraint. so, can we remove 2# 470 uF capacitor placed near to the regulator Vout side ?
Please suggest us.. waitung for your response.

Thanks & regards,
Divya

  • 0
    •  Analog Employees 
    on Mar 10, 2020 6:32 PM

    If the regulator is kept very close to the FPGA, the 4# 680uF could serve as the output caps for LTM4637. Usually, these capacitance is enough for normal operation of LTM4637. But for the system, how much capacitance are needed depends on the

    specs of the load (FPGA in your case). What is the required output voltage ripple and what is the transient requirements? These specs determine how much capacitance are needed in the system.