-.
ANALOG
t
W
DEVICES
HighPerformance
Digital-o-AnalogConverter
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PRELIMINARY TECHNICAL DATA
FEATURES
12 Bit Resolution
.
Input Register Included
Small Module Package
Programmable Output Ranges
0 to +70° C Monotonicity
Low 8ppmfC Gain TC
2J1.s
Settling Time
OBS
t
GENERAL DESCRIPTION
The DACl132 is a 12 bit, high performance digital-to-analog
converter packaged in a very compact 2" x 2" x 0.4" module.
It comes complete with an input storage register and a fast
settling output amplifier which can be jumper programmed to
produce either of five output voltage ranges. Performance
specifications include 2Jl.S
settling time to 0.01 %, 8ppm/C
gain temperatUre coefficient, :!:~LSB linearity error, and
monotonicity from 0 to +70°C.
The DACl132 combines the ADS 62 integrated circuit
DIA
with a TTL input register, an output amplifier, and a precision
reference source to form a complete converter package. The
laser trimmed ADS62 which consists of precision current
switches, and a very stable thin film resistor network provides
the DACl132 with excellent performance over temperatUre
and makes possible its small module size.
DIGITAL INPUT CHARACTERISTICS
The TTLlDTL compatible storage register contained within
the DAC1132 accepts either Binary or Offset Binary coded
inputs. Digital data appearing at the converter's 12 input ter-
minals will be strobed into the register whenever a positive
going transition is applied to the STROBE input (pin 6).
With the STROBE input held at either logic "0" or logic "1",
the input data may be changed without affecting either the
contents of the register or the output of the converter. The
transfer characteristics of the DACl132 are such that a full
scale digital input (111111111111) results in a positive full
scale voltage output.
OLE
TE
OUTPUT CHARACTERISTICS
The 12 binary-weighted current sources which form the basis
of the digital-to-analog conversion process are directly con-
trolled by the digital data stored in the input register. The
combined output of these sources is applied to the internal op
amp summing junction to produce a voltage output signal. By
connecting jumpers between the proper module pins, various
values of op amp feedback resistance and thus, output voltage
ranges can be selected.
In order to produce bipolar outputs, the current input to the
internal op amp is offset by ~ Full Scale. This offset current is
generated bv the precision internal reference source and is ap-
plied to the op amp summing junction by means of a jumper
connected betWeen appropriate module terminals.
Route 1 Industrial Park; P.O. Box 280; Norwood, Mass. 02062
Tel: 617/329-4700
TWX: 710/394-6577
West Coast
Tel: 213/595-1783
Mid-West
Tel: 312/297-87"10
t
Note: this data sheet includes "Preliminary Technical Data" describing
a new product. Though highly unlikely, it may be necessary to alter the
specifications to reflect life data collected during the initial months of
the product's use.
Information furnished by Analog Devices is believed to ba accurate
and reliable. However, no responsibilitY is assumed by Analog Devices
for its use; nor for any infringements of patents or other rights of third
panies which may result from its use. No license is granted by implica-
tion or otherwise under any patent or patent rights of Analog Devices.
~""--=_.~~
.
....-
..
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SPECIFICATIONS
@+25°C and rated supply voltages, unlessotherwise specified)
(typical
RESOLUTION
DIGITAL
INPUTS
Logic Levels
12 Bits
OV ~ Logic "0" ~ 0.8V
+2V ~ Logic "1" ~ +5V
1 Standard TTL Loadlbit
2 Standard TTL Loads
20ns (Min)
20ns (Min)
5ns
Binary
Offset Binary
0 to +5V @ lamA
0 to +10V @ 10mA
I2.5V @ 10mA
I5V @ lamA
I10V @ 10mA
2.0p.s (3.0p.s
Max) to 0.01 %T
IY2LSB
OUTLINE DIMENSIONS AND
PIN DESIGNATIONS
Dimensionsshown in inches and (mm).
8
t
Data Input Load
Strobe Input Load
Strobe Pulse Width
.
Data Setup Time
Data
---~
Hold Time
INPUT CODES
Unipolar
_..
Bipolar
--
OUTPUT RANGES
f-
~
2.01
MAX
(51.1)
-1
i]
o.41
MAX
(10.4)
0.2MIN
~""
MAX
2.01
OUTPUT IMPEDANCE
SETTLING TIME
LINEARITY ERROR
TEMPERATURE COEFFICIENT
Gain2
Unipolar Offset
Bipolar Offset2
Differential Nonlinearity
OBS
4mV/V
4mV/V
4mV/V
2p.V/V
IRLSB (Min)
I10LSB
$159
step.
include
the effects
of Reference
Voltage
f
NOTE:
Terminal pins installed only in shaded hole
locations.
Module weight: 1.6 ounces (45 grams)
All pins are gold plated half-hard brass,
(MIL-G-45204), 0.019" :to.OO1"
(0.483
:to.025mm)
dia.
For plug-in mounting card order Board
No. AC1506 @$30.
BLOCK DIAGRAM
Reference Voltage
TEMPERATURE RANGE
Operating
POWER REQUIREMENTS
I8.0ppm/C
(I10ppm/C Max)
of
Reading
I13p.V/C (I16p.V/C Max)
I2.6ppm/C
(I3.2ppm/C Max)
I2.8ppm/C
(I3.0ppm/C Max)
of
Full Scale
I5ppm/C (I12ppm/C Max)
0 to +70°C
-55°C to +lOO°C
+15V I3% @ 32mA (37mA Max)
-15V I3% @ 27mA (30mA Max)
+5V I3% @ 140mA (150mA Max)
(7mV/V Max)
(7mV/V Max)
(7mVN
Max)
(5IlV/V
Max)
OLE
TE
BIT8 14
15 BIT9
BIT7 13
BIT6 12
BITS 11
BIT410
BIT 3 9
BIT28
MSB 7
STROBE 8
GNO S
+5V 3
+15V 2
-15V 1
KEY K
21 BIPOLAR
OFFSET
22 GAIN
23 20V
ADJ.
8
-
16 BIT 10
18 LSB
17 BIT 11
POWER S.UPPLY SENSITIVITy3
Gain
Offset (unipolar)
Offset (bipolar)
Reference
AD1uSTMENTS (User Provided)
Gain
Offset
PRICE (1-9)
1 For a lOV
~
~+5V
~+15V
~-I5V
0
24
10V
25 REF. OUT
28 ANALOG
CUT
27 SUM JUNCT.
28 OFFSET
ADJUST
'=
5.1k11
2 These figures
3
Temperature
Drift.
For :tl5V supplies only with +l5V and -l5V supplies tracking.
Specifications subject to change without notice.
8
4
-2-
'8
DIGITAL INPUT DATA
All digital inputs to the DAC1132 are fully DTL/TTL com-
patible, The 12 data inputs (pins 7-18) each represent one
standard TTL load and the STROBE (pin 6) represents two
TTL loads, The converter uses Binary input code to produce
unipolar outputs and Offset Binary code to produce bipolar
outputs,
Provided that certain timing requirements are met, data ap-
pearing at the converter's input terminals is loaded into the
register by the positive-going edge of the strobe pulse, Figure
1 illustrates the required strobe timing,
DATA MUST BE STABLE~
-.<5ns
The two 5krl. feedback resistors associated with the op amp of
Figure 2 are used to determine the output voltage range. Serial
and parallel combinations of these resistors yield three different
resistance values. Table 1 shows the feedback connections used.
to obtain the various output voltage ranges.
Output Range
Unipolar Units
:t2.5V
:t5.0V
:t10V
Bipolar Units
0 to +5V
Oto+lOV
Pins jumpered Together
Pin 23 To:
Pin 26 To:
24
24
23
--
27
--
Table
1.
Range Programming Table
20ns SETUP .
MIN
:
I
MIN ~
I
I
20ns MIN
PULSE WIDTH
~OLD
~
I
OBS
I
L
20ns
,
r
'1.5V
:
I
I
:
INPUT-OUTPUT RELATIONSHIPS
Table 2 and Table 3 list the analog outputs associated with
various digital inputs for unipolar and bipolar units respectively.
DIGIT AL INPUT
NOMINAL VOLTAGE OUTPUT
0 to +5V
Range
0 to +IOV
Range
Ii
40ns
l
25ns
Figure
1.
Strobe Timing Diagram
Note that the input data must be stable for at least 20ns before
and 5ns after the pulse's leading edge. Note also that the strobe
pulse must be a minimum of 20ns wide. In order to allow ade-
quate time for the converter's analog output to settle between
conversions, the strobe frequency should be limited to 500kHz.
OUTPUT CONNECTIONS
Figure 2, below, shows the output configuration of the
DAC1132 in simplified form.
21 BIPOLAR
OFFSET
995011
0
8
23 20V RANGE
24 10V RANGE
0 TO -2mA
FROM I.C.
DIA
OLE
TE
Binary Code
111111111111
000000000001
000000000000
+4.9988V
+0.0012V
O.OOOOV
+9.9976V
+0.0024V
O.OOOOV
Table
2.
Unipolar Input-Output
Relationships
DIGIT AL INPUT
NOMINAL VOLTAGE OUTPUT
:t5V
Range
:tIOV
Range
:t2.5V
Range
25 REFERENCE OUT
26 ANALOG OUTPUT
27 SUMMING JUNCT.
28 OFFSET ADJUST
2.2M
Offset Binary Code
111111111111
100000000001
100000000000
000000000000
t-9.9951V
+2.4988V +4.9976V
0.0012V
0.0048V
0.0024V
O.OOOOV
O.OOOOV O.OOOOV
-10.0000V
-2.5000V -5.0000V
Table
3.
Bipolar Input-Output Relationships
GAIN, AND OFFSET ADJUSTMENTS
The gain and offset adjustments are made with two ex-
ternal potentiometers which the user supplies. With certain
digital inputs applied, these potentiometers are adjusted until
the desired output voltage is obtained. The voltmeter used to
measure the output must be capable of clear and stable resolu-
tion of 1/10LSB in the region of zero and full scale. The
adjustment procedure, described below, should be carefully
followed to assure optimum converter performance.
The proper connection for the offset potentiometer was shown
in Figures 3a and 3b. The gain potentiometer should be connec-
ted as shown below in Figure 4.
Figure
2.
Output Circuit
Block Diagram
External jumper connections determine whether the
DAC1132 will be a unipolar or a bipolar device. Figures 3a and
3b below show the proper connections for both configurations.
0
BIPOLAR
OFFSET
210
BIPOLAR
OFFSET
0
210-
0
0
0
REF. OUT. 250
0
0
0
0
REF. OUT. 250
0
+15V
+15V
0
OFFSET
ADJUST
CW
28
20kn
20 TURN
OFFSET
ADJUST
20kl1
20 TURN
OFFSET
ADJUST
0
GAIN
ADJ. 22
0
0
REF. OUT. 25
0
8
CW
10011
20 TURN
GAIN ADJUST
0
OFFSET
ADJUST
CW
28
a. Unipolar
-15V
b. Bipolar
-15V
Figure
3.
Unipolar/Bipolar Output Connection
-3-
--
Figure
4.
Gain Adjustment
Connection
---
--
-
For unipolar units apply a digital input of 000000000000 and
adjust the offset potentiometer until an output of OV :tl/l0LSB
is obtained.
For bipolar units apply a digital input of 000000000000 and
adjust the offset potentiometer until the negative full scale out-
put shown in Table 3 is obtained within :tl/l0LSB.
Once the appropriate offset adjustment has been made,
apply a digital input of 111111111111. Adjust the gain
potentiometer until the positive full scale output shown in
Table 2 or Table 3 is obtained within :tl/l0LSB.
POWER SUPPLY AND GROUNDING CONNECTIONS
The proper power supply and grounding connections are
shown below in Figure 5.
<15V
SUPPLY
+5V
COM
+5V
SUPPLY
The output voltage range is programmed by means of jumpers
which the user installs as shown in Figure 7.
:2:
I
I
I
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8
.,.
,...
.....
0
I
0
I
,...
N
$i
.::;:
:
z
-
I
I
I
@@
«
::
I
<3
I
I
I
@
u
KO
1
2
J
OBS
5
0
0
OUTPUT VOLTAGE RANGE
0 to +10V
0 to +5V
:t2.5V
:t5V
:tlOV
Figure
5.
Power Supply and Grounding Connections
Capacitors have been added within the DAC1132 to bypass
the :t15V and +5V power inputs. Under normal circum-
stances, no external bypass capacitors are needed.
REFERENCE OUTPUT
The +10V reference output (pin 25) is used to set the con-
verter's gain as shown in Figure 4 and to provide the offset for
bipolar devices as shown in Figure 3. It may also be used to
provide a reference voltage for otner circuits in the user's sys-
tem provided that the output current is limited. No more
than 1.5 mA should be drawn from bipolar devices and no
more than 2.5mA should be drawn from unipolar devices. Ex-
cessive current drain will degrade the converter's analog output
and could damage the internal reference source.
OLE
TE
Figure
7.
AC 1506 Range Programming
The pin connections are as shown below in Table 4.
Pin
Designation
MSB
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 8
Bit 9
Bit 10
Bit 11
Pin
A
B
C
D
E
F
H
JUMPER CONNECTION
A-C
A - C, F - H
D - E, A - C, F - H
D E,A
C
A - B, D - E
THE AC1506 MOUNTING CARD
The AC1506 mounting card is available to assist in the applica-
tion ofthe DAC1132. This 4.5" x 3.0" printed circuit card,
shown below in Figure 6, has sockets which allow a DAC1132
to be plugged directly onto it. It includes the necessary gain,
and offset adjustment potentiometers and it mates with a
Cinch 250-22-30-170 (or equivalent) edge connector which is
supplied with every card.
J
K
L
M
N
P
R
S
T
U
V
W
X
Y
Z
Designanon
Bit 12
N.C.
N.C.
Ground
Ref. Out.
Analog Out.
Strobe
+5V
+15V
-15V
Ground
8
Table
4.
AC1506 Pin Designations
3.000
(76.201
n
r
-i.
4.500
(114.301
.,'
uj
::J
Z
0
w
DAC1132
~
~
I-
z
a:
B.
8
DIMENSIONS
SHOWN
ARE IN INCHES
AND (MMI.
Figure
6.
AC1506 Outline Drawing
-4-
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