Yes, I'm looking at the LM2587S-ADJ, but would be interested in other opinions - there are a gazillion controllers available form all the semi vendors these days.
Hello.
isolated.....
Can do 2 stages:
1st stage 1:2 transformer connected to H-bridge (with 4 power N-FETs) producing double ouput voltage. Can easy run with 500kHz, open loop (add few hundred mV for diodes drop).
Output will be 10 to 32V.
(check IR chips with oscilator inside and bootstrap for "all N-FETs")
Then Buck down to 9V with old and robust Unitrode chip UC2573 and external P-FET (say 50V, 8A).
I did 10000000 Bucks with this chip - never problem.
LM2587 - need to do isolated feedback (opto or something like this...). Plus - think what to do with wide input range. (I won't use this National chip)