Hi, Sayzer

Depends on the Pic you want to use ... but, if an internal oscillator could be used ( 16F88 i.e. ) ...

you could think to change the osc. frequ by soft !!! ( 8Mhz maxi gives 500 ns ...)

but depends if you could "boost" your osc frequ. for some instructions ...

see 16F88 ( i.e.) datasheet $ 4.6.2 for further infos ...

Alain