Problems with ZXLD1350

[mellis]

Has anyone here had luck with the ZXLD1350? I'm working on an automotive application driving 3 nichia jupiters in series with a PIC doing PWM input for dimming. I can't seem to get it doing anything reliably. And.....how does one go about actually measuring amperage in these high freq power circuits? I'm using a 'true rms' meter and not getting much sense out of it. When the input V goes up, the amperage goes down...? Wave all chopped up. I followed the zetex app notes closely but still no joy.

thanks

mark e