05 for memory arrays estimate dynamic power

and an activity factor = 0.05 for memory arrays. Estimate dynamic power consumption per MHz.
Neglect wire capacitance and short-circuit current.
In 90nm process, λ =0.05μm
( )
( ) ( ) ( )
( )
( ) ( ) ( )
( )
9
log
9
2
1 10 20% 10 0.05 2 200
1 10 80% 4 0.05 2 320
0.1 200 0.05 320 1.0
36
ic
memory
dynamic
C m fF m nF
C m fF m nF
P f
mW
MHz
λ μ λ μ
λ μ λ μ
= × × • • • =
= × × • • • =
= × + × × ×
=
Problem 3
The figure below shows two cases with waveforms “a” and “b” applied to the circuit. Assume
the capacitor C
L
is initially discharged and the output time constant is very small. For each case,
find the energy characteristics at time t
1
:
1. Energy stored on the capacitor C
L
.
2. Energy dissipated in the switching transistor.
3. Total energy supplied by node b.
(Note: assume short circuit and static power dissipation are negligible)
a
b
out
C
L
V
0
b
V
0
a
V
0
V
0
b
a
Case 1
Case 2
time
time
time
time
t
1
t
1
Fig. 1. Proposed schemes for energy comparison.

Case 1
5.1 Energy stored on the capacitor C
L
(t0 is the time point where signal “a” toggles)
1 1 1
0 0 0
0
2
1
2
L
t t t
out
C VDD OUT VDD OUT L OUT
t t
VDD
L OUT OUT
L DD
dV
E i V dt i V dt C V dt
dt
C V dV
C V
= • = • = •
=
=
∫ ∫ ∫
∫
5.2 Energy dissipated in the switching transistor
1 1 1
0 0 0
0
2
( ) ( ) ( )
( )
1
2
t t t
out
Dis VDD DD OUT VDD DD OUT L DD OUT
t t
VDD
L DD OUT OUT
L DD
dV
E i V V dt i V V dt C V V dt
dt
C V V dV
C V
= • − = • − = • −
= −
=