ICL7135_14 Datasheet, PDF (4/15 Pages) Intersil Corporation – 41/2 Digit, BCD Output, A/D Converter

ICL7135
SET V_REF = 1.000V
V_REF IN
-5V
100kΩ
ANALOG
GND
100kΩ
0.47μF _27Ω
1μF
100kΩ
SIGNAL
INPUT
1μF
100K
0.1μF
+5V
ICL7135
1 V-
2 REF
UNDERRANGE ²⁸
OVERRANGE 27
3 ANALOG GND ^STROBE 26
4 INT OUT RUN/HOLD 25
5 A-Z IN DIGITAL GND 24
6 BUF OUT POLARITY 23
7 REF CAP 1 CLOCK IN 22
8 REF CAP 2
BUSY 21
9 IN LO-
LSD DI 20
10 IN HI+
D2 19
11 V+
D3 18
12 MSD D5
D4 17
13 LSB B1
MSB B8 16
14 B2
B4 15
0V
CLOCK
IN
120kHz
FIGURE 1. ICL7135 TEST CIRCUIT
V⁺
PAD
DIG GND
FIGURE 2. ICL7135 DIGITAL LOGIC INPUT
C_REF+
8
C_REF
REF HI
2
R_INT
C_{REF BUFFER}
7
6
C_AZ
V⁺
11
AUTO
ZERO
5
C_INT
INT
4
IN HI
10
INT
AZ
3
ANALOG
COMMON
9 ^INT
IN LO
AZ
DE(-) DE(+)
A/Z
-
+
INPUT
HIGH
ZI
DE(+) DE(-)
A/Z, DE(±), ZI
1
V^-
INTEGRATOR
-
+
+
AZ
COMPARATOR
INPUT
LOW
FIGURE 3. ANALOG SECTION OF ICL7135
ZERO-
CROSSING
DETECTOR
POLARITY
F/F
4
FN3093.4