網路上查到的.參考一下:- u# k% d& U: B5 H7 [2 W
"Diffusion ROM is based on VT change (using VT implant mask) => Hihg VT transistors not conducting, low VT ones conducting 4 I) Q, j5 m! Y! o4 Z+ F: |
VIA ROM is using via to "connect" or "not connect", resulting 0 and 1 - r9 V$ K$ P6 v7 aVIA ROM may have bigger cell size "
Diffusion ROM通常用在exteranl ROM; Via ROM 跟metal ROM通常是應用在embedded system; Difussion ROM的應用時間是ROM code真的很成熟的時候,這樣才可以gain到體積小而不用改ROM code的優點; Via ROM更改ROM code的cost則比較小