AD DAC08Q 8-bit, high speed, multiplying d/a converter (universal digital logic interface) Datasheet

a
8-Bit, High Speed, Multiplying D/A Converter
(Universal Digital Logic Interface)
DAC08
FEATURES
Fast Settling Output Current: 85 ns
Full-Scale Current Prematched to 61 LSB
Direct Interface to TTL, CMOS, ECL, HTL, PMOS
Nonlinearity to 0.1% Maximum Over
Temperature Range
High Output Impedance and Compliance:
–10 V to +18 V
Complementary Current Outputs
Wide Range Multiplying Capability: 1 MHz Bandwidth
Low FS Current Drift: 610 ppm/8C
Wide Power Supply Range: 64.5 V to 618 V
Low Power Consumption: 33 mW @ 65 V
Low Cost
Available in Die Form
GENERAL DESCRIPTION
The DAC08 series of 8-bit monolithic digital-to-analog converters provide very high-speed performance coupled with low cost
and outstanding applications flexibility.
Advanced circuit design achieves 85 ns settling times with very
low “glitch” energy and at low power consumption. Monotonic
multiplying performance is attained over a wide 20 to 1 reference current range. Matching to within 1 LSB between refer-
ence and full-scale currents eliminates the need for full-scale
trimming in most applications. Direct interface to all popular
logic families with full noise immunity is provided by the high
swing, adjustable threshold logic input.
High voltage compliance complementary current outputs are
provided, increasing versatility and enabling differential operation to effectively double the peak-to-peak output swing. In
many applications, the outputs can be directly converted to voltage without the need for an external op amp.
All DAC08 series models guarantee full 8-bit monotonicity, and
nonlinearities as tight as ± 0.1% over the entire operating temperature range are available. Device performance is essentially
unchanged over the ± 4.5 V to ± 18 V power supply range, with
33 mW power consumption attainable at ± 5 V supplies.
The compact size and low power consumption make the
DAC08 attractive for portable and military/aerospace applications; devices processed to MIL-STD-883, Level B are
available.
DAC08 applications include 8-bit, 1 µs A/D converters, servo
motor and pen drivers, waveform generators, audio encoders
and attenuators, analog meter drivers, programmable power
supplies, CRT display drivers, high-speed modems and other
applications where low cost, high speed and complete input/output versatility are required.
FUNCTIONAL BLOCK DIAGRAM
REV. A
Information furnished by Analog Devices is believed to be 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 parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 617/329-4700
Fax: 617/326-8703
DAC08–SPECIFICATIONS
ELECTRICAL CHARACTERISTICS (@ V = 615 V, I
S
REF
= 2.0 mA, –558C ≤ TA ≤ +1258C for DAC08/08A, 08C ≤ TA ≤ +708C for
DAC08C, E & H unless otherwise noted. Output characteristics refer to both IOUT and IOUT .)
Parameter
Symbol Conditions
Resolution
Monotonicity
Nonlinearity
Settling Time
NL
tS
Propagation Delay
Each Bit
All Bits Switched
Full-Scale Tempco1
tPLH
tPHL
TCIFS
Min
DAC08A/H
Typ
Max
8
8
Min
DAC08E
Typ
8
8
VOC
To ± 1/2 LSB,
All Bits Switched ON
or OFF, TA = 25°C1
85
± 0.1
135
85
TA = 25°C1
35
35
± 10
60
60
± 50
35
35
± 10
Full Range Current
IFR4
Full Range Symmetry
Zero-Scale Current
Output Current Range
IFRS
IZS
IOR1
IOR2
Output Current Noise
Logic Input Levels
Logic “0”
Logic Input “1”
Logic Input Current
Logic “0”
Logic Input “1”
Logic Input Swing
Logic Threshold Range
Reference Bias Current
Reference Input
Slew Rate
VIL
VIL
IIL
IIH
VIS
VTHR
I15
dI/dt
Full-Scale Current
Change <1/2 LSB,
ROUT > 20 MΩ typ
VREF = 10.000 V
R14, R15 = 5.000 kΩ
TA = +25°C
IFR4 – IFR2
R14, R15 = 5.000 kΩ
VREF = +15.0 V,
V– = –10 V
VREF = +25.0 V,
V– = –12 V
IREF = 2 mA
+18
–10
1.984 1.992
2.000
1.94
± 0.5
0.1
±4
1
Max
Units
85
± 0.39
150
Bits
Bits
% FS
ns
± 0.19
150
60
60
± 80
± 50
35
35
± 10
60
60
± 80
ns
ns
ppm/°C
+18
–10
+18
V
1.99
2.04
1.94
1.99
2.04
mA
±1
0.2
±8
2
±2
0.2
± 16
4
2.1
2.1
2.1
4.2
4.2
4.2
mA
25
25
0.8
2
VLC = 0 V
VIN = –10 V to +0.8 V
VIN = 2.0 V to 18 V
V– = –15 V
VS = ± 15 V1
DAC08C
Typ
µA
µA
mA
VLC = 0 V
25
0.8
2
–2
0.002
–10
–10
–10
10
+18
+13.5
–3
nA
0.8
V
V
–10
10
+18
+13.5
–3
µA
µA
V
V
µA
mA/µs
2
–2
0.002
–10
–10
–10
10
+18
+13.5
–3
–2
0.002
–10
–10
–1
4
8
4
REQ = 200 Ω
RL = 100 Ω
See Fast Pulsed Ref. Info Following.1
CC = 0 pF
V+ = 4.5 V to 18 V
± 0.0003 ± 0.01
V– = –4.5 V to –18 V
± 0.002 ± 0.01
IREF = 1.0 mA
–1
8
± 0.0003 ± 0.01
± 0.002 ± 0.01
± 0.0003 ± 0.01
± 0.002 ± 0.01
%∆IO/%∆V+
%∆IO/%∆V–
Power Supply Sensitivity
PSSIFS+
PSSIFS–
Power Supply Current
I+
I–
I+
I–
I+
I–
VS = ± 5 V, IREF = 1.0 mA
Pd
± 5 V, IREF = 1.0 mA
+5 V, –15 V, IREF =
2.0 mA
± 15 V, IREF = 2.0 mA
Power Dissipation
–10
Min
8
8
DAC08E
Output Voltage
Compliance
(True Compliance)
Max
VS = +5 V, –15 V,
IREF = 2.0 mA
VS = ± 15 V, IREF =
2.0 mA
4
–1
8
2.3
–4.3
2.4
–6.4
2.5
–6.5
3.8
–5.8
3.8
–7.8
3.8
–7.8
2.3
–4.3
2.4
–6.4
2.5
–6.5
3.8
–5.8
3.8
–7.8
3.8
–7.8
2.3
–4.3
2.4
–6.4
2.5
–6.5
3.8
–5.8
3.8
–7.8
3.8
–7.8
mA
mA
mA
mA
mA
mA
33
48
33
48
33
48
mW
108
135
136
174
103
135
136
174
108
135
136
174
mW
mW
NOTES
1
Guaranteed by design.
Specifications subject to change without notice.
–2–
REV. A
DAC08
TYPICAL ELECTRICAL CHARACTERISTICS
(@ VS = 615 V, and IREF = 2.0 mA, unless otherwise noted. Output
characteristics apply to both IOUT and IOUT .)
Parameter
Symbol
Conditions
Reference Input Slew Rate
Propagation Delay
Settling Time
dI/dt
tPLH, tPHL
tS
TA = 25°C, Any Bit
To +1/2 LSB, All Bits
Switched ON or OFF,
TA = 25°C
All Grades
Typical
Units
8
35
mA/µs
ns
85
ns
NOTES
For DAC08NT & GT 25°C characteristics, see DAC08N & G characteristics respectively.
Specifications subject to change without notice
ABSOLUTE MAXIMUM RATINGS 1
PIN CONNECTIONS
Operating Temperature
DAC08AQ, Q . . . . . . . . . . . . . . . . . . . . . . –55°C to +125°C
DAC08HQ, EQ, CQ, HP, EP, CP, CS . . . . . 0°C to +70°C
Junction Temperature (TJ) . . . . . . . . . . . . . . –65°C to +150°C
Storage Temperature Q Package . . . . . . . . . . –65°C to +150°C
Storage Temperature P Package . . . . . . . . . . –65°C to +125°C
Lead Temperature (Soldering, 60 sec) . . . . . . . . . . . . . . 300°C
V+ Supply to V– Supply . . . . . . . . . . . . . . . . . . . . . . . . . . 36 V
Logic Inputs . . . . . . . . . . . . . . . . . . . . . . . . V– to V– plus 36 V
VLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V– to V+
Analog Current Outputs (at VS– = 15 V) . . . . . . . . . . 4.25 mA
Reference Input (V14 to V15) . . . . . . . . . . . . . . . . . . . V– to V+
Reference Input Differential Voltage
(V14 to V15) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 18 V
Reference Input Current (I14) . . . . . . . . . . . . . . . . . . . 5.0 mA
Package Type
uJA2
uJC
Units
16-Pin Hermetic DIP (Q)
16-Pin Plastic DIP (P)
20-Contact LCC (RC)
16-Pin SO (S)
100
82
76
111
16
39
36
35
°C/W
°C/W
°C/W
°C/W
16-Pin Dual-In-Line Package
(Q Suffix)
16-Lead SO
(S Suffix)
NOTES
1
Absolute maximum ratings apply to both DICE and packaged parts, unless
otherwise noted.
2
θJA is specified for worst case mounting conditions, i.e., θJA is specified for device
in socket for cerdip, P-DIP, and LCC packages; θJA is specified for device soldered
to printed circuit board for SO package.
DAC08RC/883 20-Lead LCC
(RC Suffix)
ORDERING GUIDE1
16-Pin Dual-In-Line Package
NL
Hermetic
0.1%
DAC08AQ2
DAC08HQ
DAC08Q2
DAC08EQ
DAC08CQ
0.19%
0.39%
Plastic
LCC
DAC08HP
DAC08RC/883
DAC08EP
DAC08CP
DAC08CS3
Operating
Temperature
Range
MIL
COM
MIL
COM
COM
COM
NC = NO CONNECT
NOTES
1
Burn-in is available on commercial and industrial temperature range parts in
cerdip, plastic DIP, and TO-can packages.
2
For devices processed in total compliance to MIL-STD-883, add /883 after
part number. Consult factory for 883 data sheet.
3
For availability and burn-in information on SO and PLCC packages, contact
your local sales office.
REV. A
–3–
DAC08
WAFER TEST LIMITS (@ V = 615 V, I
S
REF = 2.0 mA, TA = 1258C for DAC08NT, DAC08GT devices; TA = 258C for DAC08N,
DAC08G and DAC08GR devices, unless otherwise noted. Output characteristics apply to both IOUT and IOUT .)
Parameter
Resolution
Monotonicity
Nonlinearity
Output Voltage
Compliance
Full-Scale Current
Full-Scale Symmetry
Zero-Scale Current
Output Current Range
Symbol
NL
VOC
IFS4 or
IFS2
IFSS
IZS
IFS1
IFS2
Logic Input “0”
Logic Input “1”
Logic Input Current
Logic “0”
Logic “1”
Logic Input Swing
Conditions
Full-Scale Current
Change < 1/2 LSB
VREF = 10.000 V
R14, R15 = 5.000 kΩ
V– = –10 V,
VREF = +15 V
V– = –12 V,
VREF = +25 V
R14, R15 = 5.000 kΩ
VIL
VIH
IIL
IIH
VIS
Reference Bias Current I15
Power Supply
PSSIFS+
Sensitivity
PSSIFS–
Power Supply Current
I+
Power Dissipation
Pd
VLC = 0 V
VIN = –10 V to +0.8 V
VIN = 2.0 V to 18 V
V– = –15 V
V+ = 4.5 V to 18 V
V– = –4.5 V to –18 V
IREF = 1.0 mA
VS = ± 15 V
IREF ≤ 2.0 mA
VS = ± 15 V
IREF ≤ 2.0 mA
DAC08NT
Limit
DAC08N
Limit
DAC08GT DAC08G DAC08GR
Limit
Limit
Limit
Units
8
8
± 0.1
+18
–10
2.04
1.94
±8
2
8
8
± 0.1
+18
–10
2.04
1.94
±8
2
8
8
± 0.19
+18
–10
2.04
1.94
±8
4
8
8
± 0.19
+18
–10
2.04
1.94
±8
4
8
8
± 0.39
+18
–10
2.04
1.94
± 16
4
Bits min
Bits min
% FS max
V max
V min
mA max
mA min
µA max
µA max
2.1
2.1
2.1
2.1
2.1
mA min
4.2
4.2
4.2
4.2
4.2
mA min
0.8
2
0.8
2
0.8
2
0.8
2
0.8
2
V max
V min
± 10
± 10
+18
–10
–3
0.01
± 10
± 10
+18
–10
–3
0.01
± 10
± 10
+18
–10
–3
0.01
± 10
± 10
+18
–10
–3
0.01
± 10
± 10
+18
–10
–3
0.01
µA max
µA max
V max
V min
µA max
% FS/% V max
3.8
–7.8
174
3.8
–7.8
174
3.8
–7.8
174
3.8
–7.8
174
3.8
–7.8
174
mA max
µA max
mW max
NOTE
Electrical tests are performed at wafer probe to the limits shown. Due to variations in assembly methods and normal yield loss, yield after packaging is not guaranteed
for standard product dice. Consult factory to negotiate specifications based on dice lot qualification through sample lot assembly and testing.
DICE CHARACTERISTICS
(+125°C Tested Dice Available)
–4–
REV. A
DAC08
Figure 1. Pulsed Reference Operation
Figure 2. Burn-in Circuit
Figure 3. Fast Pulsed Reference
Operation
Figure 4. True and Complimentary
Output Operation
REV. A
Figure 5. LSB Switching
–5–
Figure 6. Full-Scale Settling Time
DAC08 –Typical Performance Characteristics
Figure 7. Full-Scale Current
vs. Reference Current
Figure 10. Reference Amp
Common-Mode Range
Figure 13. Output Current vs.
Output Voltage (Output
Voltage Compliance)
Figure 8. LSB Propagation
Delay vs. IFS
Figure 9. Reference Input
Frequency Response
Figure 11. Logic Input Current vs.
Input Voltage
Figure 12. VTH–VLC vs. Temperature
Figure 14. Output Voltage
Compliance vs. Temperature
Figure 15. Bit Transfer Characteristics
–6–
REV. A
DAC08
Figure 16. Power Supply
Current vs. V+
Figure 17. Power Supply
Current vs. V–
Figure 18. Power Supply
Current vs. Temperature
BASIC CONNECTIONS
Figure 19. Accomodating Bipolar References
Figure 20. Basic Positive Reference Operation
Figure 21. Basic Unipolar Negative Operation
REV. A
–7–
DAC08
Figure 22. Basic Bipolar Output Operation
Figure 24. Basic Negative Reference Operation
Figure 23. Recommended Full-Scale Adjustment Circuit
Figure 25. Offset Binary Operation
–8–
REV. A
DAC08
Figure 26. Positive Low Impedance
Output Operation
Figure 27. Negative Low Impedance
Output Operation
Figure 28. Interfacing With Various Logic Families
APPLICATIONS INFORMATION
REFERENCE AMPLIFIER SET-UP
The DAC08 is a multiplying D/A converter in which the output
current is the product of a digital number and the input reference current. The reference current may be fixed or may vary
from nearly zero to +4.0 mA. The full-scale output current is a
linear function of the reference current and is given by:
IFR =
255
× IREF, where IREF = I14.
256
In positive reference applications, an external positive reference
voltage forces current through R14 into the VREF(+) terminal
(pin 14) of the reference amplifier. Alternatively, a negative reference may be applied to VREF(–) at pin 15; reference current
flows from ground through R14 into VREF(+) as in the positive
reference case. This negative reference connection has the advantage of a very high impedance presented at pin 15. The voltage at pin 14 is equal to and tracks the voltage at pin 15 due to
the high gain of the internal reference amplifier. R15 (nominally
equal to R14) is used to cancel bias current errors; R15 may be
eliminated with only a minor increase in error.
REV. A
Bipolar references may be accommodated by offsetting VREF or
pin 15. The negative common-mode range of the reference amplifier is given by: VCM– = V– plus (IREF × 1 kΩ) plus 2.5 V. The
positive common-mode range is V+ less 1.5 V.
When a dc reference is used, a reference bypass capacitor is recommended. A 5.0 V TTL logic supply is not recommended as a
reference. If a regulated power supply is used as a reference, R14
should be split into two resistors with the junction bypassed to
ground with a 0.1 µF capacitor.
For most applications the tight relationship between IREF and
IFS will eliminate the need for trimming IREF. If required,
full-scale trimming may be accomplished by adjusting the value
of R14, or by using a potentiometer for R14. An improved
method of full-scale trimming which eliminates potentiometer
T.C. effects is shown in the recommended full-scale adjustment
circuit.
Using lower values of reference current reduces negative power
supply current and increases reference amplifier negative commonmode range. The recommended range for operation with a dc
reference current is +0.2 mA to +4.0 mA.
–9–
DAC08
REFERENCE AMPLIFIER COMPENSATION FOR
MULTIPLYING APPLICATIONS
AC reference applications will require the reference amplifier to
be compensated using a capacitor from pin 16 to V–. The value
of this capacitor depends on the impedance presented to pin 14:
for R14 values of 1.0, 2.5 and 5.0 kΩ, minimum values of CC
are 15, 37, and 75 pF. Larger values of R14 require proportionately increased values of CC for proper phase margin, such that
the ratio of CC (pF) to R14 (kΩ) = 15.
For fastest response to a pulse, low values of R14 enabling small
CC values should be used. If pin 14 is driven by a high impedance such as a transistor current source, none of the above values will suffice and the amplifier must be heavily compensated
which will decrease overall bandwidth and slew rate. For R14 =
1 kΩ and CC = 15 pF, the reference amplifier slews at 4 mA/µs
enabling a transition from IREF = 0 to IREF = 2 mA in 500 ns.
Operation with pulse inputs to the reference amplifier may be
accommodated by an alternate compensation scheme. This
technique provides lowest full-scale transition times. An internal
clamp allows quick recovery of the reference amplifier from a
cutoff (IREF = 0) condition. Full-scale transition (0 mA to 2 mA)
occurs in 120 ns when the equivalent impedance at pin 14 is
200 Ω and CC = 0. This yields a reference slew rate of 16 mA/µs
which is relatively independent of RIN and VIN values.
LOGIC INPUTS
The DAC08 design incorporates a unique logic input circuit
which enables direct interface to all popular logic families and
provides maximum noise immunity. This feature is made possible by the large input swing capability, 2 µA logic input current and completely adjustable logic threshold voltage. For V– =
–15 V, the logic inputs may swing between –10 V and +18 V.
This enables direct interface with +15 V CMOS logic, even
when the DAC08 is powered from a +5 V supply. Minimum input logic swing and minimum logic threshold voltage are given
by: V– plus ( IREF × 1 kΩ) plus 2.5 V. The logic threshold may
be adjusted over a wide range by placing an appropriate voltage
at the logic threshold control pin (pin 1, VLC). The appropriate
graph shows the relationship between VLC and VTH over the
temperature range, with VTH nominally 1.4 above VLC. For
TTL and DTL interface, simply ground pin 1. When interfacing
ECL, an IREF = 1 mA is recommended. For interfacing other
logic families, see preceding page. For general set-up of the logic
control circuit, it should be noted that pin 1 will source 100 µA
typical; external circuitry should be designed to accommodate
this current.
Fastest settling times are obtained when pin 1 sees a low impedance. If pin 1 is connected to a 1 kΩ divider, for example, it
should be bypassed to ground by a 0.01 µF capacitor.
ANALOG OUTPUT CURRENTS
Both true and complemented output sink currents are provided
where IO + IO = IFS. Current appears at the “true” (IO) output
when a “1” (logic high) is applied to each logic input. As the binary count increases, the sink current at pin 4 increases proportionally, in the fashion of a “positive logic” D/A converter. When a
“0” is applied to any input bit, that current is turned off at pin 4
and turned on at pin 2. A decreasing logic count increases IO as
in a negative or inverted logic D/A converter. Both outputs may
be used simultaneously. If one of the outputs is not required it
must be connected to ground or to a point capable of sourcing
IFS; do not leave an unused output pin open.
Both outputs have an extremely wide voltage compliance enabling fast direct current-to-voltage conversion through a resistor tied to ground or other voltage source. Positive compliance
is 36 V above V– and is independent of the positive supply.
Negative compliance is given by V– plus (IREF × 1 kΩ) plus 2.5 V.
The dual outputs enable double the usual peak-to-peak load
swing when driving loads in quasi-differential fashion. This feature is especially useful in cable driving, CRT deflection and in
other balanced applications such as driving center-tapped coils
and transformers.
POWER SUPPLIES
The DAC08 operates over a wide range of power supply voltages from a total supply of 9 V to 36 V. When operating at supplies of ± 5 V or less, IREF ≤ 1 mA is recommended. Low
reference current operation decreases power consumption and
increases negative compliance, reference amplifier negative
common-mode range, negative logic input range, and negative
logic threshold range; consult the various figures for guidance.
For example, operation at –4.5 V with IREF = 2 mA is not recommended because negative output compliance would be reduced to near zero. Operation from lower supplies is possible,
however at least 8 V total must be applied to insure turn-on of
the internal bias network.
Symmetrical supplies are not required, as the DAC08 is quite
insensitive to variations in supply voltage. Battery operation is
feasible as no ground connection is required: however, an artificial ground may be used to insure logic swings, etc. remain between acceptable limits.
Power consumption may be calculated as follows:
Pd = (I+) (V+) + (I–) (V–). A useful feature of the DAC08 design
is that supply current is constant and independent of input logic
states; this is useful in cryptographic applications and further
serves to reduce the size of the power supply bypass capacitors.
TEMPERATURE PERFORMANCE
The nonlinearity and monotonicity specifications of the DAC08
are guaranteed to apply over the entire rated operating temperature range. Full-scale output current drift is low, typically
± 10 ppm/°C, with zero-scale output current and drift essentially
negligible compared to 1/2 LSB.
The temperature coefficient of the reference resistor R14 should
match and track that of the output resistor for minimum overall
full-scale drift. Settling times of the DAC08 decrease approximately 10% at –55°C; at +125°C an increase of about 15%
is typical.
The reference amplifier must be compensated by using a capacitor from pin 16 to V–. For fixed reference operation, a 0.01 µF
capacitor is recommended. For variable reference applications,
see previous section entitled “Reference Amplifier Compensation for Multiplying Applications”.
–10–
REV. A
DAC08
MULTIPLYING OPERATION
The DAC08 provides excellent multiplying performance with an
extremely linear relationship between IFS and IREF over a range
of 4 mA to 4 mA. Monotonic operation is maintained over a
typical range of IREF from 100 µA to 4.0 mA.
SETTLING TIME
The DAC08 is capable of extremely fast settling times, typically
85 ns at IREF = 2.0 mA. Judicious circuit design and careful
board layout must be employed to obtain full performance potential during testing and application. The logic switch design
enables propagation delays of only 35 ns for each of the 8 bits.
Settling time to within 1/2 LSB of the LSB is therefore 35 ns,
with each progressively larger bit taking successively longer. The
MSB settles in 85 ns, thus determining the overall settling time
of 85 ns. Settling to 6-bit accuracy requires about 65 ns to 70 ns.
The output capacitance of the DAC08 including the package is
approximately 15 pF, therefore the output RC time constant
dominates settling time if RL > 500 Ω.
Settling time and propagation delay are relatively insensitive to
logic input amplitude and rise and fall times, due to the high
gain of the logic switches. Settling time also remains essentially
constant for IREF values. The principal advantage of higher IREF
values lies in the ability to attain a given output level with lower
load resistors, thus reducing the output RC time constant.
Measurement of settling time requires the ability to accurately
resolve ± 4 µA, therefore a 1 kΩ load is needed to provide adequate drive for most oscilloscopes. The settling time fixture
shown in schematic labelled “Settling Time Measurement” uses
a cascode design to permit driving a 1 kΩ load with less than
5 pF of parasitic capacitance at the measurement node. At IREF
values of less than 1.0 mA, excessive RC damping of the output
is difficult to prevent while maintaining adequate sensitivity.
However, the major carry from 01111111 to 10000000 provides
an accurate indicator of settling time. This code change does
not require the normal 6.2 time constants to settle to within
± 0.2% of the final value, and thus settling times may be observed at lower values of IREF.
DAC08 switching transients or “glitches” are very low and may
be further reduced by small capacitive loads at the output at a
minor sacrifice in settling time.
Fastest operation can be obtained by using short leads, minimizing output capacitance and load resistor values, and by adequate
bypassing at the supply, reference and VLC terminals. Supplies
do not require large electrolytic bypass capacitors as the supply
current drain is independent of input logic states; 0.1 µF capacitors at the supply pins provide full transient protection.
Figure 30. Settling Time Measurement
REV. A
–11–
DAC08
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
N-16
16
9
1
8
PIN 1
0.280 (7.11)
0.240 (6.10)
0.325 (8.25)
0.300 (7.62) 0.195 (4.95)
0.115 (2.93)
0.060 (1.52)
0.015 (0.38)
0.210 (5.33)
MAX
0.130
(3.30)
MIN
0.160 (4.06)
0.115 (2.93)
0.100
(2.54)
BSC
0.022 (0.558)
0.014 (0.356)
000000000
0.840 (21.33)
0.745 (18.93)
0.015 (0.381)
0.008 (0.204)
0.070 (1.77) SEATING
0.045 (1.15) PLANE
Q-16
0.005 (0.13) MIN
0.080 (2.03) MAX
16
9
0.310 (7.87)
0.220 (5.59)
1
8
0.320 (8.13)
0.290 (7.37)
PIN 1
0.060 (1.52)
0.015 (0.38)
0.840 (21.34) MAX
0.200 (5.08)
MAX
0.200 (5.08)
0.125 (3.18)
0.023 (0.58)
0.014 (0.36)
0.100
(2.54)
BSC
0.150
(3.81)
MIN
SEATING
0.070 (1.78) PLANE
0.030 (0.76)
0.015 (0.38)
0.008 (0.20)
15°
0°
SO-16
0.3937 (10.00)
0.3859 (9.80)
16
9
1
8
0.0688 (1.75)
0.0532 (1.35)
PIN 1
0.0098 (0.25)
0.0040 (0.10)
SEATING
PLANE
0.0500
(1.27)
BSC
0.2550 (6.20)
0.2284 (5.80)
0.0192 (0.49)
0.0138 (0.35)
0.0196 (0.50)
x 45°
0.0099 (0.25)
0.0099 (0.25)
0.0075 (0.19)
8°
0°
0.0500 (1.27)
0.0160 (0.41)
PRINTED IN U.S.A.
0.1574 (4.00)
0.1497 (5.80)
E-20
0.358 (9.09)
0.342 (8.69)
SQ
0.075
(1.91)
REF
0.100 (2.54)
0.064 (1.63)
0.095 (2.41)
0.075 (1.90)
TOP
VIEW
0.358
(9.09)
MAX
SQ
0.011 (0.28)
0.007 (0.18)
R TYP
0.075 (1.91)
REF
0.200 (5.08)
BSC
0.100 (2.54) BSC
3
19
18 20
4
0.028 (0.71)
0.022 (0.56)
1
BOTTOM
VIEW
14
13
0.015 (0.38)
MIN
0.050 (1.27)
BSC
8
9
45° TYP
0.088 (2.24)
0.054 (1.37)
0.055 (1.40)
0.045 (1.14)
–12–
0.150 (3.81)
BSC
REV. A