EPROM SENSE circuit issue

[yanggeng007]

EPROM SENSE question

Hi,
ALL
I have a EPROM SENSE cirucit as follow,
------------VDD(5v)
|
_|
GND!--->| |_ PMOS w/l=1u/20u
|
|---sense line---->to a inverter
|
_|
2v bias->| |_ NMOS w/l=20u/1u
|
|
_|
wl pulse->|||_ Float gate cell w/l=0.6u/0.5u
|
------ gnd!
that is the bit line path, when read , cell current is about 10ua,
wl pulse =5v , sense line voltage is about 0.1v showed by Hspice simulation,
but the silicon can't work, I am confused!!!
Any good idea is appreciated,

 

[yanggeng007]

Re: EPROM SENSE question

The FIG is following:
MP1 size is about 1u/20u.
V bias=2.2v, Vth MN1 is about=1v,
Icell1 is about=10uA,
The cell is not programmed.Vthcell=2v
But when the Vwl=5v,Vysel=5v, Vbias=2.2v
the Vsense is always about=4.0~4.5v, Confused!!