8. MMOOSS NNOORR RROOMM LLaayyoouutt
BL0 BL1 BL2 BL3
Cell (9.5 x 7)
WL0
WL1
WL2
WL3
Programmming using the
Active Layer Only
Polysilicon
Metal1
Diffusion
Metal1 on Diffusion
GND
GND
9. MMOOSS NNOORR RROOMM LLaayyoouutt
Cell (11 x
Programmming using
the Contact Layer Only
Polysilicon
Metal1
Diffusion
Metal1 on Diffusion
7)
10. MMOOSS NNAANNDD RROOMM
VDD
Pull-up devices
BL [0] BL[1] BL[2] BL [3]
WL[0]
WL[1]
WL[2]
WL[3]
All word lines high by default with exception of selected row
11. No contact to VDD or GND necessary;
drastically reduced cell size
Loss in performance compared to NOR ROM
MMOOSS NNAANNDD RROOMMC
LLLe
al
al (
yyy8
oox
uu7
tt )
Programmming using
the Metal-1 Layer Only
Polysilicon
Diffusion
Metal1 on Diffusion
14. DDeeccrreeaassiinngg WWoorrdd LLiinnee DDeellaayy
Driver
WL Polysilicon word line
Metal word line
(a) Driving the word line from bothsides
Metal bypass
WL K cells
(b) Using a metal bypass
Polysilicon word line
(c) Use silicides
15. PPrreecchhaarrggeedd MMOOSS NNOORR RROOMM
f pre
VDD
Precharge devices
WL [0]
WL [1]
GND
WL [2]
WL [3]
GND
BL [0] BL [1] BL [2] BL [3]
PMOS precharge device can be made as large as necessary,
but clock driver becomes harder to design.
16. Source Drain
tox
tox
n+ p n+_
NNoonn--VVoollaattiillee MMeemmoorriieess
TThhee FFllooaattiinngg--ggaattee ttrraannssiissttoorr
((FFAAMMOOSS))
Floating gate Gate
Substrate
Device cross-section Schematic symbol
D
G
S
17. 10 V 5 V 20 V
S D
-5 V 0 V
S D
-2.5 V 5 V
S D
FFllooaattiinngg--GGaattee TTrraannssiissttoorr
PPrrooggrraammmmiinngg
20 V 0 V 5 V
Avalanche injection Removing programming
voltage leaves charge trapped
Programming results in
higher VT.
27. SSttaattiicc CCAAMM MMeemmoorryy CCeellll
Bit
Word
Bit Bit Bit
Bit
M8
M4
Bit
M9
M5
M6 M7
Word
Word
Match
S S
int
M3 M2
M1
Wired-NOR Match Line
CAM
••••••
•••
•••
CAM
CAMCAM
28. HitLogic
Sense Amps / Input Drivers
SRAM
ARRAY
CAM
ARRAY
AddressDecoder
Input Drivers
CCAAMM iinn CCaacchhee MMeemmoorryy
Address Tag Hit R/W Data
39. SSeennssee AAmmpplliiffiieerrss
C V
make V as smallas
possible
tp = ----------------
Iav
large
Idea: Use Sense Amplifer
small
outputinput
s.a.
small
transition