ENAD Formula Sheet
ENAD Formula Sheet
ENAD Formula Sheet
LC
General
solutions
to
natural
response
of
second-order
circuits
2
2
Overdamped
response,
0 <
x t = A1e s1t + A2e
s2t
s1 , s2 = 2
02
02 > 2
Underdamped
response,
x ( t ) = B1e t cos d
t + B2e t sin d t
s1 , s2 = jd
02 = 2
Critically
damped
response,
t
+ D2e t
x t = D1te
s1 = s2 =
()
()
General
solutions
to
step
response
of
second-order
circuits
2
2
Overdamped
response,
0 <
x t = X f + A '1
e s1t + A '2 e s2t
s1 , s2 =
2 02
2
2
Underdamped
response,
0 >
x t = X f + B '1
e t cos d t
+ B '2 e
t sin d t
s , s = j
1 2
d
02 = 2
Critically
damped
response,
t
t
()
()
x ( t ) = X f + D '1 te
s1 = s2 =
22
+ D '2 e
Distinct
Real
Roots
Repeated
Real
Roots
Distinct
Complex
Roots
Repeated
Complex
Roots
Useful
Transform
Pairs
F(s)
K
s+a
Ke at u ( t )
(s + a)
K
s + j
K
( s + j )
f(t)
Kte at u ( t )
2 K e t cos ( t + ) u ( t )
s + + j
K
( s + + j )
2t K e t cos ( t + ) u ( t )
Convolution
Integral
y ( t ) = h ( t )
x ( t ) = x ( t ) h (t )
y ( t ) = h ( t )
x ( t ) = h ( ) x ( t ) d
y (t ) = x (t ) h (t ) =
x ( ) h (t ) d
Frequency
selective
circuits
General
form
of
transfer
function
for
low-pass
filters
K
H (s) =
General
form
of
transfer
function
for
high-pass
filter
Ks
H (s) =
s + C
General
form
of
transfer
function
for
band-pass
filter
s
H ( s ) =
2
2
General
form
of
transfer
function
for
band-reject
filter
s 2 + 02
H (s) = K
s + s + 0
s + C
23
s 2 + s + 02
Magnitude
of
transfer
function,
defined
at
at
cutoff
frequency,
C
H ( jC ) =
1
H max
2
Cutoff
frequencies
of
bandpass
and
bandreject
filters
2
C1 ,C1 = + 2 + o
Two
Port
Terminal
Equations
V1 = z11 I1 + z12 I 2
V2 = b11V1 b12 I1
V2 = z21 I1 + z22 I 2
I 2 = b21V1 b22 I1
I1 = y11V1 + y12V2
V1 = h11 I1 + h12V2
I 2 = y21V1 + y22V2
I 2 = h21 I1 + h22V2
V1 = a11V2 a12 I 2
I1 = g11V1 + g12 I 2
I1 = a21V2 a22 I 2
V2 = g 21V1 + g 22 I 2
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25
26
27
Transformers
(positive
dot
convention)
M = k L1L2
di
di
v1 = L1 1 + M 2
dt
dt
N2
v1
N1
N
i2 = 1 i1
N2
v2 =
v2 = M
di1
di
+ L2 2
dt
dt
N2
v1
N1
N
i2 = ! 1 i1
N2
v2 = !
28