ICL7107CPLZ Intersil, ICL7107CPLZ Datasheet - Page 8

• Manufacturer Part Number: ICL7107CPLZ
• Description: IC ADC 3.5DIGIT LCD/LED 40DIP
• Manufacturer: Intersil

Specifications of ICL7107CPLZ

• Display Type: LED
• Configuration: 7 Segment
• Digits Or Characters: A/D 3.5 Digits
• Voltage - Supply: 4.75 V ~ 5.25 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Through Hole
• Package / Case: 40-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Supply: -
• Interface: -
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

Digital Section
Figures 7 and 8 show the digital section for the ICL7106 and
ICL7107, respectively. In the ICL7106, an internal digital
ground is generated from a 6V Zener diode and a large
P-Channel source follower. This supply is made stiff to
FIGURE 6. EXCLUSIVE ‘OR’ GATE FOR DECIMAL POINT DRIVE
ICL7106
†
ONE INVERTER SHOWN FOR CLARITY
TEST
V+
THREE INVERTERS
TYPICAL SEGMENT OUTPUT
INTERNAL DIGITAL GROUND
BP
DECIMAL
SELECT
0.5mA
2mA
POINT
V+
SEGMENT
8
OUTPUT
CD4030
OSC 1
GND
V+
FROM COMPARATOR OUTPUT
40
ICL7106, ICL7107, ICL7107S
FIGURE 7. ICL7106 DIGITAL SECTION
†
TO LCD
DECIMAL
POINTS
TO SWITCH DRIVERS
OSC 2
CLOCK
39
COUNTER
1000’s
OSC 3
b
a
absorb the relative large capacitive currents when the back
plane (BP) voltage is switched. The BP frequency is the
clock frequency divided by 800. For three readings/sec., this
is a 60Hz square wave with a nominal amplitude of 5V. The
segments are driven at the same frequency and amplitude
and are in phase with BP when OFF, but out of phase when
ON. In all cases negligible DC voltage exists across the
segments.
Figure 8 is the Digital Section of the ICL7107. It is identical to
the ICL7106 except that the regulated supply and back plane
drive have been eliminated and the segment drive has been
increased from 2mA to 8mA, typical for instrument size
common anode LED displays. Since the 1000 output (pin 19)
must sink current from two LED segments, it has twice the
drive capability or 16mA.
In both devices, the polarity indication is “on” for negative
analog inputs. If IN LO and IN HI are reversed, this indication
can be reversed also, if desired.
COUNTER
SEGMENT
DECODE
38
e
LCD PHASE DRIVER
f
100’s
INTERNAL
d
7
GROUND
g
DIGITAL
a
÷
4
c
LATCH
b
c
SEGMENT
COUNTER
DECODE
e
f
10’s
7
d
g
LOGIC CONTROL
a
c
b
SEGMENT
COUNTER
DECODE
e
f
V
1’s
TH
7
d
g
a
= 1V
c
b
21
÷
200
500Ω
BACKPLANE
6.2V
37
26
1
V+
TEST
V-
FN3082.8