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Honored Contributor
Honored ContributorPower schematic for Cyclone IV
Hi, i am designing a very simple development board and need some tips on Cyclone IV power design. The board will be used for learning purposes with simpled designes. It is not aimed for very fast dei...
Altera_ForumHonored Contributor
Honored ContributorHello, Dave!
Your answers regarding the usage of 1117 LDOs to power Cyclone IV seem to be controversial: ---------------------------------------------------------------------------------- --- Quote Start --- The 3.3v, 2.5v and 1.2v are generated with standard 1117 ldos with a bypassing 22uF tantalum capacitor. --- Quote End --- --- Quote Start --- this design looks good to me. --- Quote End --- ---------------------------------------------------------------------------------- --- Quote Start --- Why Power Supply on "Cyclone IV GX FPGA Development Kit" is so sophisticated? why not use simple 3-pin ldo instead of multi-pin Linear Regulators used on this Kit? --- Quote End --- --- Quote Start --- FPGAs have a power-on requirement that the power rails ramp in a well-defined time period. Multi-pin linear regulators generally have enable and soft-start functions that can be used to aid in power-on sequencing. a simple 3-pin linear regulator does not provide this functionality. --- Quote End --- ----------------------------------------------------------------------------------
