Data Sheet

12
FIGURE 13. ICL7107 WITH AN EXTERNAL BAND-GAP
REFERENCE (1.2V TYPE)
FIGURE 14. ICL7107 WITH ZENER DIODE REFERENCE
FIGURE 15. ICL7106 AND ICL7107: RECOMMENDED
COMPONENT VALUES FOR 2V FULL SCALE
FIGURE 16. ICL7107 OPERATED FROM SINGLE +5V
Typical Applications (Continued)
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40
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26
25
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OSC 1
OSC 2
OSC 3
TEST
REF HI
REF LO
C
REF
C
REF
COMMON
IN HI
IN LO
A-Z
BUFF
INT
V-
G2
C3
A3
G3
GND
100pF
TO PIN 1
SET V
REF
= 100mV
0.1µF
0.01µF
1MΩ
100kΩ
1kΩ 10kΩ
IN
+
47kΩ
0.47µF
TO DISPLAY
IN LO is tied to supply COMMON establishing the correct common mode
voltage. If COMMON is not shorted to GND, the input voltage may floa
t
with respect to the power supply and COMMON acts as a pre-regulato
r
for the reference. If COMMON is shorted to GND, the input is single
ended (referred to supply GND) and the pre-regulator is overridden.
10kΩ
1.2V (ICL8069)
V
-
V+
-
0.22µF
Since low TC zeners have breakdown voltages ~ 6.8V, diode must
be placed across the total supply (10V). As in the case of Figure 14,
IN LO may be tied to either COMMON or GND.
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40
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35
34
33
32
31
30
29
27
26
25
24
23
22
21
OSC 1
OSC 2
OSC 3
TEST
REF HI
REF LO
C
REF
C
REF
COMMON
IN HI
IN LO
A-Z
BUFF
INT
V -
G2
C3
A3
G3
GND
100pF
TO PIN 1
SET V
REF
= 100mV
0.1µF
0.01µF
1MΩ
100kΩ
1kΩ 100kΩ
IN
+
-
47kΩ
0.22µF
0.47µF
TO DISPLAY
+5V
-5V
6.8V
28
40
39
38
37
36
35
34
33
32
31
30
29
27
26
25
24
23
22
21
OSC 1
OSC 2
OSC 3
TEST
REF HI
REF LO
C
REF
C
REF
COMMON
IN HI
IN LO
A-Z
BUFF
INT
V -
G2
C3
A3
G3
BP/GND
100pF
TO PIN 1
SET V
REF
= 100mV
0.1µF
0.01µF
1MΩ
100kΩ
25kΩ 24kΩ
IN
+
-
470kΩ
0.22µF
0.047µF
TO DISPLAY
V+
V-
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40
39
38
37
36
35
34
33
32
31
30
29
27
26
25
24
23
22
21
OSC 1
OSC 2
OSC 3
TEST
REF HI
REF LO
C
REF
C
REF
COMMON
IN HI
IN LO
A-Z
BUFF
INT
V -
G2
C3
A3
G3
GND
100pF
TO PIN 1
SET V
REF
= 100mV
0.1µF
0.01µF
1MΩ
100kΩ
1kΩ 10kΩ
IN
+
-
47kΩ
0.22µF
0.47µF
TO DISPLAY
An external reference must be used in this application, since the
voltage between V+ and V- is insufficient for correct operation of the
internal reference.
15kΩ
1.2V (ICL8069)
+5V
ICL7106, ICL7107, ICL7106S, ICL7107S