Homework #1

Diode Parameters:
Diode turn-on voltage: .7V
Reverse Saturation Current: 10nA
Transistor Parameters:
k’ = 160μA/V2
VT0 = 0.55V
VDSAT=0.55V PT =
μn = 400 cm2/V*s 20 =
=s (c 1)
Cox = 4 fF/μm2

Problem 1
↑

For the 2 circuit in Figure 1, calculate the values of the labeled voltage V and current I.
DI OFF DON
⑨ If If DrOFF Dr ON
①
,

② If DON . DON ,

I = 0
I
zid
I5-00 8 m
=
0

5 -
1-5) =
10
.

5 -
0 .
7 -
c -

5) = 0 . 62mA
I =

10k+ 5k
[1(5k 00k) + = 10 5 510
-
.

86) -
0 .
7 Di Pr
Da D2
V =
5+ 0 62 (5) =
-1 92
o
.
=
.

69mA
-

F2(104) -15) = 0
of
[1 = 0 .
② If DION ,
Dron
Iz JoA 01
= 0
5
.

69(10k)
-

-
540 .
=
1
7 21 = = 0 .
43 mA
10k
.

El = 0 86 -
0
5 = 0 .
3 MA
(5) (-5)
. .

43(10) In 0
7
=

5
-

0. -
0 .
-

V = 1 .
] ,
I =
0 V =
(5) + 5(10k) 0 = 0
Figure 1 Iz ImA # 43 mA
.
=
0.

Problem 2

For the circuit in Figure 2, the input source is sinusoidal with a frequency of 10 KHZ and ·

peak amplitude of 5 volts applied at node A. Draw the voltage waveforms at node B and C
respectively for at least one complete cycle.
Node C :

Node B :
f

-
t
A

V
+zVpn ~ bot

*A
- -

+
-
zVDon-
~ -
-
-

Figure 2
If Va > K zVDon +
,
D I & D-OFF .
Ds & Do ON If VA > Vc+ 2 Vion ,
D & D2 OFF ,
Ds@DpON
VB =
V c + 2 Don = 2 .

rV 1 Vc =
Up-2Voon
If VA < V+ con , DidDzON ,
D> & DpOFF If Va < Vc + zDon ,
D & DzON ,
Da & Dr OFF
VB -zVDon Vu 0
4 v
=
= =
-1 .
 Problem 3

For the circuit shown in Figure 3, calculate the currents ID1, ID2, ID3, and ID4 at D1, D2, and
D3 respectively. Also, calculate the voltages Vo.
Nu = 0
V = 0 - 0
. = - o .
7)
70
9) (-8) 22 Ipp == In
↓ it
d
.

I =
1 SmA
.

281 zor jo zon

Iz
8
TOI + Ipr
-
0
=
1 ) mA .

Y = V
"
[Dz =
4 -
0 .
825 =
3 . 195mA
4 MA
=
=

A
#
old
=> 201 7 3 195
3 4
125nAx
= -
=
. .

Vy = -
0 ,
yu "
( -0 7) . -
( -

8)
2z =
=
1 .
825mA
4k
Figure 3
ID3 = 1 825
.
-

1 = 0 .
85mA
Problem 4

a) For the circuit shown in Figure 4.a, assuming long channel device, determine the minimum
allowable VDD such that M1 remains in triode.

b) For the circuit in Figure 4.b, S

i. Calculate the drain current and output voltage for R1=1K, and 10K. State how the drain
current and output voltage change by increasing the load resistance R1. Assume M1 is
a long channel device with W = 8μm and L = .8μm
ii. Repeat part i assuming short channel device. (b) (i) Ip = (E) (Vb-ve)
+1.8v
(9) Ups(VGs Ve 1 0 55 0 45V -
=
1-8-VD
-

= x160x (p-0 5572

11
.

In = Eros-Ve) Vp = 1 .
32V

( (b)
: 1 8-1 32
R1 Ip 48 MA
.
.

(0 45)
= = 0.
=
1k
.

900mA 9m A D Vout 18-Vx(V-05

&
VDD = In XRD M1 VD = 0 .
89V
9x18 80 89
1
In orglm
.

S
= 0.
.

=
x 500 =

45
(i) = x160x (VD-
= 0 .

MinVop = 0 .
45+ 0 .
45 = 0 .

gr
Figure 4.a Figure 4.b VD =
1, 29 v

ID =
1 .

8 129 = 0 .
504mA

8-V = x16xx(V
1
55)(1
:

- 0 .
+
(v)
V = 0 .
88V
1 88
2 Ip
80
. .

092 m
=
= 0 .