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COMPILED MEMORY
CHARACTERISTICS FOR TIMING AND POWER
Samsung ASIC
5-3
STD150
CHARACTERISTICS FOR TIMING AND POWER
STD150 compiled memories are fully optimized under 1.2V
±
0.1V supply voltage. compiled memory in this
section has been characterized using typical-process at 25 degree and 1.2V supply. The values of
worst-case and best-case can be calculated by using the local derating factor derived from the following
equation:
t
WC
(t
BC
) = K
P_local
×
K
V_local
×
K
T_local
×
t
NOM
Where,
t
WC
is a worst-case propagation delay
t
BC
is a best-case propagation delay
t
NOM
is a typical-case propagation delay characterized under typical-process, 25 degree and 1.2V supply
K
P_local
is a local process factor corresponding to each memory type.
K
V_local
is a local voltage derating factor corresponding to each memory type.
K
T_local
is a local temperature derating factor corresponding to each memory type.
Note that
K
P_local
,
K
V_local
and
K
T_local
are only used in compiled memories.
A two-dimensional timing table look-up model has been adopted to yield more accuracy. Based on the
combination of input slopes and output loads, the propagation delay is measured from the input crossing
50% V
DD
to the output crossing 50% V
DD
. The timing values reported in the tables are also taken from the
same voltage level as the switching characteristics with 0.2ns for input slope and 10SL(Standard Load) for
output load.
In STD150, four kinds of power consumptions are available-the dynamic read power consumption, the
dynamic write power consumption, the standby power consumption and the static leakage power
consumption. The dynamic power consumption for read mode and write mode is measured on the condition
that 50% switching activities for all inputs are applied except that OEN (Output Enable Negative) is tied to
low. The total power consumption can be calculated by the following equation:
P
total
= ((2
×
SA
read
×
P
read
) + (2
×
SA
write
×
P
write
))
×
f
MAX
Where,
P
total
is the total power consumption in microwatts
P
read
is the read power consumption in microwatts per MHz
P
write
is the write power consumption in microwatts per MHz
SA
read
is the input switching activity under a read access on every cycle
SA
write
is the input switching activity under a write access on every cycle
f
MAX
is the memory clock frequency in MHz.