® ®
Figure 1. ADS-112 Functional Block Diagram
DATEL, Inc., 11 Cabot Boulevard, Mansfield, MA 02048-1151 (U.S.A.) • Tel: (508) 339-3000 Fax: (508) 339-6356 • For immediate assistance: (800) 233-2765
ADS-112
12-Bit, 1MHz, Low-Power
Sampling A/D Converters
FEATURES
• 12-bit resolution
• No missing codes
• 1MHz minimum sampling rate
• Functionally complete
• Small 24-pin DDIP
• Low-power, 1.3 Watts
• Three-state output buffers
• Samples to Nyquist frequencies
GENERAL DESCRIPTION
DATEL’s ADS-112 is a 12-bit, functionally complete, sampling
A/D converter that is packaged in a space-saving 24-pin DDIP.
Requiring ±15V and +5V supplies, a minimum sampling rate of
1MHz is achieved while only dissipating 1.3 Watts. The
ADS-112 digitizes signals up to Nyquist frequencies. Models
are available for use in either commercial (0 to + 70°C) or
military (–55 to +125°C) operating temperature ranges.
Typical applications include spectrum, transient, vibration and
waveform analysis. This device is also ideally suited for radar,
sonar, video digitization, medical instrumentation and high-
speed data acquisition systems.
INPUT/OUTPUT CONNECTIONS
PIN FUNCTION PIN FUNCTION
1 BIT 12 (LSB) 24 –15V SUPPLY
2 BIT 11 23 ANALOG GROUND
3 BIT 10 22 +15V SUPPLY
4 BIT 9 21 +10V REFERENCE
5 BIT 8 20 BIPOLAR
6 BIT 7 19 ANALOG INPUT
7 BIT 6 18 COMP BIN
8 BIT 5 17 ENABLE (1-12)
9 BIT 4 16 START CONVERT
10 BIT 3 15 EOC
11 BIT 2 14 DIGITAL GROUND
12 BIT 1 (MSB) 13 +5V SUPPLY
REF
RE
GI
ST
ER
RE
GI
ST
ER 3-S
TA
TE
O
UT
PU
T R
EG
IS
TE
R
12 BIT 1 (MSB)
11 BIT 2
10 BIT 3
9 BIT 4
8 BIT 5
7 BIT 6
6 BIT 7
5 BIT 8
4 BIT 9
3 BIT 10
2 BIT 11
1 BIT 12 (LSB)
TIMING AND
CONTROL LOGIC
BIPOLAR 20
+10V REF. 21
START CONVERT 16
EOC 15
DI
GI
TA
L C
OR
RE
CT
IO
N
LO
GI
C
DAC
FLASH
ADC
COMP BIN 18
BUFFER
–
+
S/H
ANALOG INPUT 19
17 ENABLE (1-12)
S2
S1
13
+5V SUPPLY
22
+15V SUPPLY
23
ANALOG GROUND
14
DIGITAL GROUND
24
–15V SUPPLY