Part Number:LMZM33606
Hello,
I'm planning to use LMZM3360x series power modules in both Buck and IBB configurations. Hence i need a psu without noise and ripple, i will use LDOs after them. Here is general info,
19V Input => LMZM33606, +12.6V, 4.4A out
19V Input => LMZM33606, -12,6V 3.2A out
19V Input => LMZM33602, +5,6V 1,1A out
Here are my questions,
1) I know suggested max operation frequency is 1.2MHz and datasheet says above this, effiency will drop. But how much drop there is gonna be? I want to increase Fsw to 2MHz cause LDOs' PSRR values are not good at 1MHz ( around 15dB).
Webench does not allow me to do it but when i change Rt value, i can get 2MHz. Does this effect other components' values? Can i get these amount of current with 2MHz switching frequency?
2) I've checked a few designs in TI forum and Webench values for input and output capacitors are lower than these designs. For example, in evaluation board there are 39uF Alu + 2x 4.7uF ceramic input caps and 4x 47uF + 150uF Tantalum output caps. But when i try to use Webench, it suggests using 2x10uF input caps (de-rated 8,6uF) and 4x22uF output caps ( de-rated 56uF).
These values are vastly different from evaluation board. Should i add Aluminum or Tantalum caps at the input and output? Also maybe increaseing ceramic caps values? What should be my caps values in total for this applications?
Thank you in advance.
