Philips Semiconductors
CMOS 8-bit A/D converters
Product data
ADC0803/0804
+5 V
VCC 40
SCN8051
OR
SCN80C51
1 P1.0
2 P1.1
3 P1.2
4 P1.3
5 P1.4
6 P1.5
7 P1.6
8 P1.7
17 RD
16 WR
12 INTO
39 P0.0
D0 18
D1 17
D2 16
D3 15
D4 14
D5 13
D6 12
D7 11
VCC 20
A/D
RD 2
WR 3
INTR 5
CS 1
19 CLK R
4 CLK IN
10 kΩ
56 pF
6 VIN(+)
7 VREF/2
ANALOG
INPUTS
12 A GND
11 D GND
18 D0
17 D1
16 D2
15 D3
14 D4
A/D
13 D5
12 D6
11 D7
8–BIT
BUFFER
N74LS241
N74LS244
N74LS541
DATA
BUS
OE
SL00029
Figure 14. Buffering the A/D Output to Drive High Capacitance
Loads and for Driving Off-Board Loads
Figure 13. SCN8051 Interfacing
SL00028
+5 V
Ct
4.7 kΩ
1.5 kΩ
18 kΩ
820 Ω
NE5521
1µF
LVDT
4.7 kΩ
0.47 µF
22 kΩ
470 Ω
IN4148
VIN(+)
3.3 kΩ
2 kΩ
VIN(–)
VCC
+5 V
A/D
2 kΩ
VREF/2
FULL SCALE
100 Ω ADJUST
2 kΩ
SL00030
Figure 15. Digitizing a Transducer Interface Output
2002 Oct 17
13