網路上查到的.參考一下:7 m# _* A) v& U1 B5 U* h" |
"Diffusion ROM is based on VT change (using VT implant mask) => Hihg VT transistors not conducting, low VT ones conducting 7 v; J! M8 l4 d( t. L
VIA ROM is using via to "connect" or "not connect", resulting 0 and 1 ; G( t4 d) I+ _, Q5 C0 O& w- 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