3-1/2 DIGIT A/D CONVERTERS
1
2
3
4
5
6
7
8
TC14433
TC14433A
0.1 µF
0.1 µF
470k
C
14024B
R
–V
C0
C0
R
R /C C
1 1 1
1
2
1
V
x
DS
DS
DS
DS
Q
Q
Q
Q
+V
4
3
2
1
0
1
2
3
V
AG
27k
20k
TC14433
V
TC04
REF
R
EOC DU
R
V
V
V
DD SS EE
C
C
14070B 1/4
+V
300k
+V
–V
14013B
14070B
1/4
D
C
Q
Q
1/2 DIGIT
R
R
14013B
PLUS
SIGN
+V
+V
D
C
Q
Q
BI D C B A PhLD
BI D C B A PhLD
14543B
BI D C B A PhLD
14543B
+V
–V
R
R
+V
–V
14543B
1/4 14070B
–V
–V
g
f
e d c b a
g
f
e d c b a
g f e d c b a
MINUS
SIGN
+V
Figure 11. 3-1/2 Digit Voltmeter with LCD Display
≈
16,400 CLOCK CYCLES
BETWEEN EOC PULSES
EOC
1/2 CLOCK CYCLE
18 CLOCK CYCLES
DS
1
1/2 DIGIT
(MSD)
2 CLOCK
CYCLES
DS
2
DS
3
DS
4
(LSD)
Figure 12. Digit Select Timing Diagram
TELCOM SEMICONDUCTOR, INC.
3-133