®
®
ADS-945
14-Bit, 10MHz
Sampling A/D Converters
FEATURES
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14-bit resolution
10MHz minimum throughput
Functionally complete
No missing codes
Low power, 4.0W
Excellent dynamic performance
Internally clamped input
Edge triggered
TTL compatible
2" x 4" module
Very low profile
INPUT/OUTPUT CONNECTIONS
PIN
1
4
5-6
7
8
9
10-11
12
13
14
15-17
18
19-25
26
27
28
29
30
31
32
33
34
35
36
37
38
FUNCTION
ANALOG GROUND
ANALOG INPUT
ANALOG GROUND
+10V REFERENCE OUT
ANALOG GROUND
GAIN ADJUST
DO NOT CONNECT
–15V SUPPLY
ANALOG GROUND
+15V SUPPLY
ANALOG GROUND
OFFSET ADJUST
ANALOG GROUND
MISSING PIN
DIGITAL GROUND
DIGITAL GROUND
T/H STATUS
T/H STATUS
DIGITAL GROUND
START CONVERT
OVERFLOW
OUTPUT ENABLE (OE)
DIGITAL GROUND
NO CONNECT
DIGITAL GROUND
DIGITAL GROUND
PIN
70-76
69
64-68
63
62
61
58-60
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
FUNCTION
ANALOG GROUND
+5V ANALOG SUPPLY
ANALOG GROUND
–5.2V ANALOG SUPPLY
ANALOG GROUND
NO CONNECT
DIGITAL GROUND
–5.2V DIGITAL SUPPLY
DO NOT CONNECT
+5V DIGITAL SUPPLY
DIGITAL GROUND
BIT 1 (MSB)
BIT 2
BIT 3
BIT 4
BIT 5
BIT 6
BIT 7
BIT 8
BIT 9
BIT 10
BIT 11
BIT 12
BIT 13
BIT 14 (LSB)
DIGITAL GROUND
GENERAL DESCRIPTION
The low-cost ADS-945 is a high-performance, 14-bit, 10MHz
sampling A/D converter. This device accurately samples
full-scale input signals up to Nyquist frequencies with no
missing codes. The dynamic performance of the ADS-945
has been optimized to achieve a THD of –80dB and a
SNR of 75dB.
Packaged in a 2" x 4" module, the functionally complete
ADS-945 contains a fast-settling sample/hold amplifier, a
subranging (two-pass) A/D converter, a precise voltage
reference, timing/control logic, three-state outputs, and
error-correction circuitry. Digital inputs and outputs are TTL
compatible (except for pins 29 and 30 which are ECL).
Requiring ±15V, +5V and –5.2V supplies, the ADS-945 typically
dissipates 4.0W. The unit is offered with a bipolar input range
of ±1.25V. Models are available for use in either commercial
(0 to +70°C) or military (–55 to +125°C) operating temperature
ranges. Typical applications include radar signal analysis,
medical/graphic imaging, and FFT spectrum analysis.
33 OVERFLOW
BUFFER
ANALOG INPUT 4
+1
T/H
53 BIT 1 (MSB)
FLASH
ADC
1
52 BIT 2
DIGITAL CORRECTION LOGIC
3-STATE OUTPUT REGISTER
51 BIT 3
50 BIT 4
49 BIT 5
48 BIT 6
47 BIT 7
46 BIT 8
45 BIT 9
44 BIT 10
43 BIT 11
42 BIT 12
41 BIT 13
40 BIT 14 (LSB)
GAIN ADJUST 9
+10 REF. OUT 7
CASE
1,2,3,5,6,8,13,15,17,
19-25,62,64-68,70-76
ANALOG GROUND
OFFSET ADJUST 18
AGND
GAIN
CIRCUIT
REF
DAC
Σ
DGND
OFFSET
CIRCUIT
AMP
FLASH
ADC
2
START CONVERT 32
T/H STATUS 29
T/H STATUS 30
TIMING AND
CONTROL LOGIC
34 OUTPUT ENABLE
26 MISSING PIN
10,11,56 DO NOT CONNECT
12
–15V
SUPPLY
14
+15V
SUPPLY
27,28,31,35,37-39,54,58-60
DIGITAL
GROUND
36, 61
NO
CONNECT
55
+5V DIGITAL
SUPPLY
57
–5.2V DIGITAL
SUPPLY
Figure 1. ADS-945 Functional Block Diagram
DATEL, Inc., 11 Cabot Boulevard, Mansfield, MA 02048-1151 (U.S.A.)
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Tel: (508) 339-3000 Fax: (508) 339-6356
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For immediate assistance: (800) 233-2765
MURATA-PS [ MURATA POWER SOLUTIONS INC. ]
