DAS1151_15 Datasheet, PDF (3/4 Pages) Analog Devices – LOW LEVEL INPUT 12 BIT DATA ACQUISITION MODULES

+IN
+15V ₄
36 +15V
-15V
34 -15V
+-IINN 397:t: ANALOGIN
RG
SHA
4
OUT
-IN
10pF
SOLID
TANTALUM
{^,,'
4
RRGG4431. .1-"-}.'
+15V 0.1
.
{_{:J .-r ~.} ^ANALOG
COMMON
-,5VO
.l
r
+5VO
CLOCK
CONVERT
COMMAND
STATUS
STATUS
SERIALOUT
22 ANAGND
20 SHAOUT
r------,
AA,, 5501.'-1"" ^i.N2"?:GTl, I
SHACONTROL53
g~~'J~6 0
~
MSB
MSB
BIT 2
.,8 SUM
REFERENCE
OUT
OFFSET ADJ
SUMMING
O^POINT
BIT 3
BIH
BITS
BIT.
BIT 7
BIT a
BITS
BIT 'A
BIT 11
LSB
REFERENCE IN
BIPOLAR OFFSET
10V SPAN
20V SPAN
B _{., Figure 2. DAS1150 Block Diagram and Pin Designations}
S _{GROUNDING PRACTICE}
O _{Attention should be given to the methods of connection for}
L ^{electrical returns and voltage reference points. Analog ground}
and digital ground are provided. These data acquisition systems
E _{do not have an internal connection between analog ground and}
T ^{digital ground and, thus, a connection must be provided in the}
E ^{external circuitry. The choice of an optimum "star" point for}
loon
15 TURN
GAIN
ADJUSTMENT
17 REF OUT
+5V 56
16 ZERO
CONV COM 57
15 REF IN
14 BIIN
.,3 10V
12 20V
STATUS 58
STATUS 59.
OGL :
3
11 ANAGNO
.7 MSB
.6 MSB
.5 BIT2
.4 BIT3
.3 BIT4
.2 BIT5
BIT6
SERIAL 66.
LSB 67.
BIT 11 68.
BIT 10 69.
BIT 9 70.
BIT 8 71.
BIT 7 72.
BOTTOM VIEW
NOTES,
'THESE PINS APPEAR ON DAS1150 ONLY.
'THESE PINS APPEAR ON DAS1151 ONLY.
'ANALOG AND DIGITAL GROUNDS SHOULD BE
TIED TOGETHER AT ONE POINT AS CLOSETO
THE MODULE AS POSSIBLE.
'SHOULD BE LOCATED WITHIN 1" FROM MODULE.
Figure 3. Module Connections for:!: 10V Range
Figure 3 shows the connections required to operate the
DAS1150 or DAS1151 with a :!:10V input range. Table 1
these grounds is an important consideration in the performance
shows connections for ADC input ranges.
of the system. No strict rules can be given, only the general
guidelines that the grounding should be arranged in such a
manner as to avoid ground loops and to minimize the coupling
of voltage drops between the high current carrying logic sup-
ply ground and the sensitive analog circuit sections.
1. If the :!:15V power supply is floating (for optimum analog
Input Range
0 to +5V
:!:2.5V
0 to +10V
:!:5V
:!:10V
Jumper
Pin 17 to 15, Pin 20 to 18
Pin 17 to 14, Pin 20 to 18
Pin 17 to 15, Pin 20 to 13
Pin 17 to 14, Pin 20 to 13
Pin 17 to 14, Pin 20 to 12
accuracy), connect its common to analog ground. If the
:!:15V power supply is not floating, connect its common to
Table 1. ADC Input Range Connections
digital ground.
70
2. Connect the +5V supply common to digital ground. If this
supply also powers additional equipment, run separate,
60
parallel returns to the equipment ground and to digital
ground.
50
3. Single-ended input signals should only be returned to anaiog
ground. If this is not possible, then connect the input sig-
._"- 40
I
nals in the differential configuration.
~
4. Connect computer ground to digital ground. Use heavy wire
;:: 30
or ground planes.
20
5. The computer chassis should be connected to the computer
and power supply grounds at only one point.
10
6. Connect the third wire ground from main ac power input
to the computer power supply return.
7. Bias return path should always be provided.
ol
1
GAIN
Figure4. Typical Settling Time Curvesfor DAS1150