Elenco Electronics EP-130 - Miller Integrating Circuit

-95
-
Y
ou
k
now t
h
at an
LED
prompt
l
y
ligh
ts w
h
en you tur
n
i
t on.
Y
ou can a
l
so
ligh
t
i
t up
g
ra
d
ua
ll
y.
I
n t
hi
s pro
j
ect
,
you
’ll
b
e a
bl
e to o
b
serve t
h
e
LED
s s
l
ow
l
y get
b
r
i
g
h
ter
w
hil
e you
h
o
ld
d
own t
h
e
k
ey.
This circuit arran
g
ement is called a Miller inte
g
ratin
g
c
ircuit. The output of the circuit increases as its inpu
t
rises. The integrating circuit increases the value o
f
the 10
0
μ
F capacitor above its actual value. When
you press the key, the LEDs become brighter and th
e
c
apacitor char
g
es slowly throu
g
h resistor R. Settin
g
the switch to position B dischar
g
es the capacitor, an
d
the LEDs turn o
ff.
Before completin
g
the project, set the switch to
position B, to dischar
g
e the capacitor.
S
et the switch
to pos
i
t
i
on
B
an
d
h
o
ld
t
h
e
k
ey
d
own to watc
h
LEDs
1
, 2, and 3 become brighter. In about 5 seconds the
y
will reach maximum brightness. Now set the switc
h
to
B
to
di
sc
h
arge t
h
e capac
i
tor, t
h
en
h
o
ld
d
own t
h
e
k
ey to
d
o t
h
e exper
i
ment aga
i
n.
No
t
es
:
EXPERIMENT #76: MILLER INTEGRATING CIRCUI
T
S
chemati
c
Wirin
g
S
equence
:

31
-
63
-
122
-
137

32-34

35
-
3
7

38
-72

7
1
-
6
7-
116
-
133

68
-
90
-11
5
-1
32

69
-124-11
9

7
0
-
121

89
-
138