FPO

FPO 41%

Monolithic 12-Bit

DIGITAL-TO-ANALOG CONVERTERS

FEATURES

INDUSTRY STANDARD PINOUT

FULL

10V SWING WITH V

12VDC

DIGITAL INPUTS ARE TTL- AND
CMOS-COMPATIBLE

GUARANTEED SPECIFICATIONS WITH

12V AND

15V SUPPLIES

1/2LSB MAXIMUM NONLINEARITY:

C to +70

SETTLING TIME: 4

s max to

0.01% of

Full Scale

GUARANTEED MONOTONICITY:
0

C to +70

TWO PACKAGE OPTIONS: Hermetic side-
brazed ceramic and low-cost molded
plastic

DESCRIPTION

This monolithic digital-to-analog converter is pin-for-
pin equivalent to the industry standard DAC80 first
introduced by Burr-Brown. Its single-chip design in-
cludes the output amplifier and provides a highly
stable reference capable of supplying up to 2.5mA to
an external load without degradation of D/A perfor-
mance.

This converter uses proven circuit techniques to pro-
vide accurate and reliable performance over tempera-
ture and power supply variations. The use of a buried
zener diode as the basis for the internal reference
contributes to the high stability and low noise of the
device. Advanced methods of laser trimming result in
precision output current and output amplifier feedback

resistors, as well as low integral and differential lin-
earity errors. Innovative circuit design enables the
DAC80 to operate at supply voltages as low as

11.4V

with no loss in performance or accuracy over any
range of output voltage. The lower power dissipation
of this 118-mil by 121-mil chip results in higher
reliability and greater long term stability.

Burr-Brown has further enhanced the reliability of the
monolithic DAC80 by offering a hermetic, side-brazed,
ceramic package. In addition, ease of use has been
enhanced by eliminating the need for a +5V logic
power supply.

For applications requiring both reliability and low
cost, the DAC80P in a molded plastic package offers
the same electrical performance over temperature as
the ceramic model. The DAC80P is available with
voltage output only.

For designs that require a wider temperature range, see
Burr-Brown models DAC85H and DAC87H.

DAC80
DAC80P

International Airport Industrial Park · Mailing Address: PO Box 11400 · Tucson, AZ 85734 · Street Address: 6730 S. Tucson Blvd. · Tucson, AZ 85706

Tel: (520) 746-1111 · Twx: 910-952-1111 · Cable: BBRCORP · Telex: 066-6491 · FAX: (520) 889-1510 · Immediate Product Info: (800) 548-6132

Reference

Control

Circuit

12-Bit

Resistor

Ladder

Network

and

Current

Switches

Digital Inputs

Reference

Gain
Adjustment

Scaling
Network

Analog
Output

Offset
Adjustment
+ Supply

Supply

1986 Burr-Brown Corporation

PDS-643F

Printed in U.S.A. July, 1993

DAC80/80P

DAC80

PARAMETER

MIN

TYP

MAX

UNITS

DIGITAL INPUT
Resolution

Bits

Logic Levels (0

C to +70

(1)

(Logic "1")

+16.5

VDC

(Logic "0")

+0.8

VDC

= +2.4V)

+20

= +0.4V)

180

ACCURACY (at +25

Linearity Error

1/4

1/2

LSB

Differential Linearity Error

1/2

3/4

LSB

Gain Error

(2)

0.1

0.3

Offset Error

(2)

0.05

0.15

% of FSR

(3)

DRIFT (0

C to +70

(4)

Total Bipolar Drift (includes gain, offset, and linearity drifts)

ppm of FSR/

Total Error Over 0

C to +70

(5)

Unipolar

0.06

0.15

% of FSR

Bipolar

0.06

0.12

% of FSR

Gain: Including Internal Reference

ppm/

Excluding Internal Reference

ppm/

Unipolar Offset

ppm of FSR/

Bipolar Offset

ppm of FSR/

Differential Linearity 0

C to +70

1/2

3/4

LSB

Linearity Error 0

C to +70

1/4

1/2

LSB

Monotonicity Guaranteed

+70

CONVERSION SPEED, V

OUT

Models

Settling Time to

0.01% of FSR

For FSR Change (2k

|| 500pF Load)

with 10k

Feedback

with 5k

Feedback

For 1LSB Change

Slew Rate

CONVERSION SPEED, I

OUT

Models

Settling Time to

0.01% of FSR

For FSR change: 10

to 100

Load

300

Load

ANALOG OUTPUT, V

OUT

Models

Ranges

Output Current

(6)

Output Impedance (DC)

0.05

Short Circuit to Common, Duration

(7)

Indefinite

ANALOG OUTPUT, I

OUT

Models

Ranges: Bipolar

0.96

1.0

1.04

Unipolar

1.96

2.0

2.04

Output Impendance: Bipolar

2.6

3.2

3.7

Unipolar

4.6

6.6

8.6

Compliance

2.5

+2.5

REFERENCE VOLTAGE OUTPUT

+6.23

+6.30

+6.37

External Current (constant load)

2.5

Drift vs Temperature

ppm/

Output Impedance

POWER SUPPLY SENSITIVITY
V

12VDC or

15VDC

0.002

0.006

% FSR/ % V

POWER SUPPLY REQUIREMENTS

11.4

16.5

VDC

Supply Drain (no load): +V

Power Dissipation (V

15VDC)

345

480

TEMPERATURE RANGE
Specification

+70

Operating

+85

Storage: Plastic DIP

+100

Ceramic DIP

+150

SPECIFICATIONS

ELECTRICAL

Typical at +25

C and

= 12V or 15V unless otherwise noted.

NOTES: (1) Refer to "Logic Input Compatibility" section. (2) Adjustable to zero with external trim potentiometer. (3) FSR means full scale range and is 20V for

10V range,

10V for

5V range for V

OUT

models; 2mA for I

OUT

models. (4) To maintain drift spec, internal feedback resistors must be used. (5) Includes the effects of gain, offset

and linearity drift. Gain and offset errors externally adjusted to zero at +25

C. (6) For

less than

12VDC, limit output current load to

2.5mA to maintain

10V full

scale output voltage swing. For output range of

5V or less, the output current is

5mA over entire

range. (7) Short circuit current is 40mA, max.

2.5,

10, +5, +10

DAC80/80P

FUNCTIONAL DIAGRAM AND PIN ASSIGNMENTS

ABSOLUTE MAXIMUM RATINGS

PACKAGE INFORMATION

NOTE: (1) For detailed drawing and dimension table, please see end of data
sheet, or Appendix D of Burr-Brown IC Data Book.

PACKAGE DRAWING

MODEL

PACKAGE

NUMBER

(1)

DAC80P

24-Pin Plastic DIP

167

DAC80

24-Pin Ceramic DIP

125

to Common ...................................................................... 0V to +18V

to Common ......................................................................... 0V to 18

Digital Data Inputs to Common .............................................. 1V to +18V
Reference Output to Common ............................................................

Reference Input to Common ...............................................................

Bipolar Offset to Common ...................................................................

10V Range R to Common ...................................................................

20V Range R to Common ...................................................................

External Voltage to DAC Output .............................................. 5V to +5V
Lead Temperature (soldering, 10s) ................................................ +300

Max Junction Temperature .............................................................. 165

Thermal Resistance,

: Plastic DIP ........................................... 100

C/W

Ceramic DIP ......................................... 65

C/W

Stresses above those listed under "Absolute Maximum Ratings" may
cause permanent damage to the device. Exposure to absolute maxi-
mum conditions for extended periods may affect device reliability.

NOTE: (1) Logic supply applied to this pin has no effect.

(MSB) Bit 1

Bit 2

Bit 3

Bit 4

Bit 5

Bit 6

Bit 7

Bit 8

Bit 9

Bit 10

Bit 11

(LSB) Bit 12

6.3V Ref Out

Gain Adjust

Common

Summing Junction

20V Range

10V Range

Bipolar Offset

Ref Input

OUT

(1)

Reference

Control

Circuit

12-Bit

Resistor

Ladder

Network

and

Current

Switches

(MSB) Bit 1

Bit 2

Bit 3

Bit 4

Bit 5

Bit 6

Bit 7

Bit 8

Bit 9

Bit 10

Bit 11

(LSB) Bit 12

6.3V Ref Out

Gain Adjust

Common

Scaling Network

Bipolar Offset

Ref Input

OUT

(1)

Reference

Control

Circuit

12-Bit

Resistor

Ladder

Network

and

Current

Switches

Voltage Models

Current Models

6.3k

BURN-IN SCREENING

Burn-in screening is an option available for the models
indicated in the Ordering Information table. Burn-in dura-
tion is 160 hours at the maximum specified grade operating
temperature (or equivalent combination of time and tem-
perature).

All units are tested after burn-in to ensure that grade speci-
fications are met. To order burn-in, add "BI" to the base
model number.

ORDERING INFORMATION

MODEL

PACKAGE

OUTPUT

DAC80-CBI-I

Ceramic DIP

Current

DAC80Z-CBI-I

Ceramic DIP

Current

DAC80-CBI-V

Ceramic DIP

Voltage

DAC80Z-CBI-V

Ceramic DIP

Voltage

DAC80P-CBI-V

Plastic DIP

Voltage

BURN-IN SCREENING OPTION

BURN-IN TEMP.

MODEL

PACKAGE

(160h)

(1)

DAC80-CBI-V-BI

Ceramic DIP

+125

DAC80P-CBI-V-BI

Plastic DIP

+125

NOTE: (1) Or equivalent combination. See text.

DAC80/80P

OUT

Ref In

Bipolar Offset

Scale 10V FSR

Scale 20V FSR

Scale

COM

Gain Adjust

6.3V Ref Out

PAD

FUNCTION

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 (LSB)

PAD

FUNCTION

Substrate Bias: Isolated. NC: No Connection

MECHANICAL INFORMATION

MILS (0.001")

MILLIMETERS

Die Size

118 x 121

3.0 x 3.07

0.13

Die Thickness

0.51

0.08

Min. Pad Size

4 x 4

0.10 x 0.10

Metalization

Aluminum

OUT

Ref In

Bipolar Offset

Scale 10V FSR

Scale 20V FSR

Sum Junct

COM

Gain Adjust

6.3V Ref Out

PAD

FUNCTION

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 (LSB)

PAD

FUNCTION

Substrate Bias: Isolated. NC: No Connection

MECHANICAL INFORMATION

MILS (0.001")

MILLIMETERS

Die Size

118 x 121

3.0 x 3.07

0.13

Die Thickness

0.51

0.08

Min. Pad Size

4 x 4

0.10 x 0.10

Metalization

Aluminum

DAC80KD-V DIE TOPOGRAPHY

DAC80KD-I DIE TOPOGRAPHY

DICE INFORMATION

DAC80/80P

DISCUSSION OF
SPECIFICATIONS

DIGITAL INPUT CODES

The DAC80 accepts complementary binary digital input
codes. The CBI model may be connected by the user for any
one of three complementary codes: CSB, COB, or CTC (see
Table I).

ACCURACY

Linearity of a D/A converter is the true measure of its
performance. The linearity error of the DAC80 is specified
over its entire temperature range. This means that the analog
output will not vary by more than

1/2LSB, maximum, from

an ideal straight line drawn between the end points (inputs
all "1"s and all "0"s) over the specified temperature range of
0

C to +70

Differential linearity error of a D/A converter is the devia-
tion from an ideal 1LSB voltage change from one adjacent
output state to the next. A differential linearity error speci-
fication of

1/2LSB means that the output voltage step sizes

can range from 1/2LSB to 3/2LSB when the input changes
from one adjacent input state to the next.

Monotonicity over a 0

C to +70

C range is guaranteed in the

DAC80 to insure that the analog output will increase or
remain the same for increasing input digital codes.

DRIFT

Gain Drift is a measure of the change in the full scale range
output over temperature expressed in parts per million per

C (ppm/

C). Gain drift is established by: 1) testing the end

point differences for each DAC80 model at 0

C, +25

C, and

+70

C; 2) calculating the gain error with respect to the 25

value, and; 3) dividing by the temperature change. This
figure is expressed in ppm/

C and is given in the electrical

specifications both with and without internal reference.

Offset Drift is a measure of the actual change in output with
all "1"s on the input over the specified temperature range.
The offset is measured at 0

C, +25

C, and 70

C. The

maximum change in Offset is referenced to the Offset at
25

C and is divided by the temperature range. This drift is

expressed in parts per million of full scale range per

C (ppm

of FSR/

C).

SETTLING TIME

Settling time for each DAC80 model is the total time
(including slew time) required for the output to settle within
an error band around its final value after a change in input
(see Figure 1).

Voltage Output Models

Three settling times are specified to

0.01% of full scale

range (FSR); two for maximum full scale range changes of
20V, 10V and one for a 1LSB change. The 1LSB change is
measured at the major carry (0111...11 to 1000...00), the
point at which the worst case settling time occurs.

Current Output Models

Two settling times are specified to

0.01% of FSR. Each is

given for current models connected with two different resis-
tive loads: 10

to 100

and 1000

to 1875

. Internal

resistors are provided for connecting nominal load resis-
tances of approximately 1000

to 1800

for output voltage

range of

1V and 0 to 2V (see Figures 11 and 12).

COMPLIANCE

Compliance voltage is the maximum voltage swing allowed
on the current output node in order to maintain specified
accuracy. The maximum compliance voltage of all current
output models is

2.5V. Maximum safe voltage range of

1V and 0 to 2V (see Figures 11 and 12).

POWER SUPPLY SENSITIVITY

Power supply sensitivity is a measure of the effect of a
power supply change on the D/A converter output. It is
defined as a percent of FSR per percent of change in either
the positive or negative supplies about the nominal power
supply voltages (see Figure 2).

REFERENCE SUPPLY

All DAC80 models are supplied with an internal 6.3V
reference voltage supply. This voltage (pin 24) has a toler-
ance of

1% and must be connected to the Reference Input

DIGITAL INPUT

ANALOG OUTPUT

CSB

COB

CTC

(1)

Complementary

Complementary Complementary

Straight

Offset

Two's

MSB

LSB

Binary

Complement

000000000000

+Full Scale

1LSB

011111111111

+1/2 Full Scale

Zero

Full Scale

100000000000

1/2 Full Scale 1LSB

1LSB

Full Scale

111111111111

Zero

Full Scale

Zero

NOTE: (1) Invert the MSB of the COB code with an external inverter to obtain

CTC code.

TABLE I. Digital Input Codes.

FIGURE 1. Full Scale Range Settling Time vs Accuracy.

0.1

Settling Time (µs)

100

Accuracy

Percent of Full-Scale Range (%)

0.3

0.1

0.03

0.01

0.003

0.001

to 100

1000

to 1875

10k

Feedback

V Models

I Models

DAC80/80P

(pin 16) for specified operation. This reference may be used
externally also, but external current drain is limited to
2.5mA.

If a varying load is to be driven, an external buffer amplifier
is recommended to drive the load in order to isolate bipolar
offset from load variations. Gain and bipolar offset adjust-
ments should be made under constant load conditions.

LOGIC INPUT COMPATIBILITY

DAC80 digital inputs are TTL, LSTTL and 4000B,
54/74HC CMOS compatible. The input switching threshold
remains at the TTL threshold over the entire supply range.

Logic "0" input current over temperature is low enough to
permit driving DAC80 directly from outputs of 4000B and
54/74C CMOS devices.

OPERATING INSTRUCTIONS

POWER SUPPLY CONNECTIONS

Connect power supply voltages as shown in Figure 3. For
optimum performance and noise rejection, power supply
decoupling capacitors should be added as shown. These
capacitors (1

F tantalum) should be located close to the

DAC80.

12V OPERATION

All DAC80 models can operate over the entire power supply
range of

11.4V to

16.5V. Even with supply levels drop-

ping to

11.4V, the DAC80 can swing a full

10V range,

provided the load current is limited to

2.5mA. With power

supplies greater than

12V, the DAC80 output can be loaded

up to

5mA. For output swing of

5V or less, the output

current is

5mA, minimum, over the entire V

range.

No bleed resistor is needed from +V

to pin 24, as was

needed with prior hybrid Z versions of DAC80. Existing

12V applications that are being converted to the monolithic

DAC80 must omit the resistor to pin 24 to insure proper
operation.

EXTERNAL OFFSET AND GAIN ADJUSTMENT

Offset and gain may be trimmed by installing external Offset
and Gain potentiometers. Connect these potentiometers as
shown in Figure 3 and adjust as described below. TCR of the
potentiometers should be 100ppm/

C or less. The 3.9M

and 10M

resistors (20% carbon or better) should be lo-

cated close to the DAC80 to prevent noise pickup. If it is not
convenient to use these high value resistors, an equivalent
"T" network, as shown in Figure 4, may be substituted.

FIGURE 2. Power Supply Rejection vs Power Supply Ripple.

FIGURE 3. Power Supply and External Adjustment Connection Diagrams.

Reference

Control

Circuit

12-Bit

Resistor

Ladder

Network

and

Current

Switches

Reference

Control

Circuit

12-Bit

Resistor

Ladder

Network

and

Current

Switches

Voltage Output Models

Current Output Models

6.3k

3.9M

1µF

0.01µF

10k

100k

10k

100k

10M

3.9M

0.01µF

10k

100k

10k

100k

10M

1µF

100

10k

100k

0.1

0.01

0.001

0.0001

Power Supply Ripple Frequency (Hz)

% of FSR Error per % of Change in V

DAC80/80P

Existing applications that are converting to the monolithic
DAC80 must change the gain trim resistor on pin 23 from
33M

to 10M

to insure sufficient adjustment range. Pin

23 is a high impedance point and a 0.001

1F to 0.01

ceramic capacitor should be connected from this pin to
Common (pin 21) to prevent noise pickup. Refer to Figure
5 for relationship of Offset and Gain adjustments to unipolar
and bipolar D/A operation.

Unipolar

Offset Adjustment

For unipolar (CSB) configurations, apply the digital input
code that should produce zero potential output and adjust the
Offset potentiometer for zero output.

For bipolar (COB, CTC) configurations, apply the digital
input code that should produce the maximum negative
output. Example: If the Full Scale Range is connected for
20V, the maximum negative output voltage is 10V. See
Table II for corresponding codes.

Gain Adjustment

For either unipolar or bipolar configurations, apply the
digital input that should give the maximum positive output.
Adjust the Gain potentiometer for this positive full scale
output. See Table II for positive full scale voltages and
currents.

Bipolar

+ Full Scale

All Bits
Logic 1

1LSB

Range
of Offset
Adjust

Offset Adjust Translates the Line

Digital Input

All Bits

Logic 0

Range of
Gain Adjust

Analog Output

Gain Adjust

Rotates the Line

Full Scale Range

+ Full Scale

All Bits
Logic 1

1LSB

Range of
Offset Adjust

Offset Adjust Translates the Line

Digital Input

Full Scale

Range of
Gain Adjust

Analog Output

Gain Adjust

Rotates the Line

Full Scale

Range

Bipolar

Offset

MSB On,
All Others
Off

All Bits
Logic 0

FIGURE 5. Relationship of Offset and Gain Adjustments for

a Unipolar and Bipolar D/A Converter.

ANALOG OUTPUT

DIGITAL INPUT

VOLTAGE

(1)

CURRENT

MSB

LSB

0 to +10V

10V

0 to 2mA

1mA

000000000000

+9.9976V

+9.9951V

1.9995mA

0.9995mA

011111111111

+5.0000V

0.0000V

1.0000mA

0.0000mA

100000000000

+4.9976V

0.0049V

0.9995mA

+0.0005mA

111111111111

0.0000V

10.0000V

0.0000mA

+1.000mA

One LSB

2.44mV

4.88mV

0.488

NOTE: (1) To obtain values for other binary ranges:

0 to +5V range divide 0 to +10V range values by 2.

5V range: divide

10V range values by 2.

2.5V range: divide

10V range values by 4.

TABLE II. Digital Input/Analog Output.

VOLTAGE OUTPUT MODELS

Output Range Connections

Internal scaling resistors provided in the DAC80 may be
connected to produce bipolar output voltage ranges of

10V,

5V, or

2.5V; or unipolar output voltage ranges of 0 to

+5V or 0 to +10V. See Figure 6.

Gain and offset drift are minimized because of the thermal
tracking of the scaling resistors with other internal device
components. Connections for various output voltage ranges
are shown in Table III. Settling time for a full-scale range
change is specified as 4

s for the 20V range and 3

s for the

10V range.

FIGURE 6. Output Amplifier Voltage Range Scaling Circuit.

6.3k

(1)

Summing
Junction

Reference Input

To Reference Control Circuit

NOTE: (1) Resistor Tolerances: ±2% max.

Common

Bipolar
Offset

Output

From Weighted
Resistor
Network

10M

270k

7.8k

to 10k

3.9M

180k

10k

FIGURE 4. Equivalent Resistances.

DAC80/80P

CURRENT OUTPUT MODELS

The resistive scaling network and equivalent output circuit
of the current model differ from the voltage model and are
shown in Figures 7 and 8.

Internal scaling resistors (Figure 7) are provided to scale an
external op amp or to configure load resistors for a voltage
output. These connections are described in the following
sections.

If the internal resistors are not used for voltage scaling,
external R

(or R

) resistors should have a TCR of

25ppm/

C or less to minimize drift. This will typically add

50ppm/

C plus the TCR of R

(or R

) to the total drift.

Driving An External Op Amp

The current output model DAC80 will drive the summing
junction of an op amp used as a current-to-voltage converter
to produce an output voltage. See Figure 9.

OUT

= I

OUT

where I

OUT

is the DAC80 output current and R

is the

feedback resistor. Using the internal feedback resistors of

Output

Digital

Connect

Range

Input Codes

Pin 15 to Pin 17 to

Pin 19 to

Pin 16 to

COB or CTC

2.5V

COB or CTC

0 to +10V

CSB

0 to +5V

CSB

TABLE III. Output Voltage Range Connections for Voltage

Models.

6.3k

(1)

Reference Input

To Reference Control Circuit

NOTE: (1) Resistor Tolerances: ±2% max.

(1)

FIGURE 7. Internal Scaling Resistors.

FIGURE 8. Current Output Model Equivalent Output Circuit.

To
Reference
Control
Circuit

24 Reference Out

17 Bipolar Offset

21 Common

15 I

OUT

16 Reference Input

6.6k

6.3k

6.3V

0 to

2mA

FIGURE 9. External Op-Amp--Using Internal Feedback

Resistors.

6.6k

OUT

0 to
2mA

OPA604

(1)

10V Range

20V Range

OUT

NOTE: (1) For fast settling.

the current output model DAC80 provides output voltage
ranges the same as the voltage model DAC80. To obtain the
desired output voltage range when connecting an external op
amp, refer to Table IV.

Output

Digital

Connect

Range

Input Codes

A to

Pin 17 to

Pin 19 to

Pin 16 to

10V

COB or CTC

2.5V

COB or CTC

0 to +10V

CSB

0 to +5V

CSB

TABLE IV. Voltage Range of Current Output.

Output Larger Than 20V Range

For output voltage ranges larger than

10V, a high voltage

op amp may be employed with an external feedback resistor.
Use I

OUT

value of

1mA for bipolar voltage ranges and

2mA for unipolar voltage ranges. See Figure 10. Use
protection diodes when a high voltage op amp is used.

The feedback resistor, R

, should have a temperature coef-

ficient as low as possible. Using an external feedback
resistor, overall drift of the circuit increases due to the lack
of temperature tracking between R

and the internal scaling

resistor network. This will typically add 50ppm/

C plus R

drift to total drift.

FIGURE 10. External Op-Amp--Using External Feedback
Resistors.

6.6k

6.3k

0 to

2mA

6.3k

BB3582J

(1)

NOTE: (1) For output voltage swings up to 290V p-p.

OUT

DAC80/80P

Driving a Resistive Load Unipolar

A load resistance, R

= R

+ R

, connected as shown in

Figure 11 will generate a voltage range, V

OUT

, determined

by:

The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes
no responsibility for the use of this information, and all use of such information shall be entirely at the user's own risk. Prices and specifications are subject to change
without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant
any BURR-BROWN product for use in life support devices and/or systems.

OUT

= 2mA [(R

)

+ R

)]

The unipolar output impedance R

equals 6.6k

(typ) and

is the internal load resistance of 968

(derived by

connecting pin 15 to 20 and pin 18 to 19). By choosing R

= 210

, R

= 1178

. R

in parallel with R

yields 1k

total

load. This gives an output range of 0 to 2V. Since R

is not

exact, initial trimming per Figure 3 may be necessary; also
R

may be trimmed.

Driving a Resistive Load Bipolar

The equivalent output circuit for a bipolar output voltage
range is shown in Figure 12, R

= R

+ R

. V

OUT

determined by:

OUT

1mA [(R

)

+ R

)]

By connecting pin 17 to 15, the output current becomes
bipolar (

1mA) and the output impedance R

becomes

3.2k

(6.6k

in parallel with 6.3k

). R

is 1200

(derived

by connecting pin 15 to 18 and pin 18 to 19). By choosing
R

= 225

, R

= 1455

. R

in parallel with R

yields 1k

total load. This gives an output range of

1V. As indicated

above, trimming may be necessary.

FIGURE 12. Current Output Model Connected for Bipolar

Output Voltage with Resistive Load.

+1mA

OUT

Current Controlled
by Digital Input

Common

FIGURE 11. Current Output Model Equivalent Circuit

Connected for Unipolar Voltage Output with
Resistive Load.

0 to

2mA

OUT

Current Controlled
by Digital Input

Common

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: DAC80-CBI-V

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: DAC80-CBI-V