Page 1
Pin Programmable
a
FEATURES
Four Programmable Output Voltages:
10.000 V, 7.500 V, 5.000 V, 2.500 V
Laser-Trimmed to High Accuracies
No External Components Required
Trimmed Temperature Coefficient:
5 ppm/8C max, 08C to +708C (AD584L)
15 ppm/8C max, –558C to +125°C (AD584T)
Zero Output Strobe Terminal Provided
Two Terminal Negative Reference
Capability (5 V & Above)
Output Sources or Sinks Current
Low Quiescent Current: 1.0 mA max
10 mA Current Output Capability
MIL-STD-883 Compliant Versions Available
GENERAL DESCRIPTION
The AD584 is an eight-terminal precision voltage reference offering pin-programmable selection of four popular output voltages: 10.000 V, 7.500 V, 5.000 V and 2.500 V. Other output
voltages, above, below or between the four standard outputs, are
available by the addition of external resistors. Input voltage may
vary between 4.5 and 30 volts.
Laser Wafer Trimming (LWT) is used to adjust the pin-programmable output levels and temperature coefficients, resulting
in the most flexible high precision voltage reference available in
monolithic form.
In addition to the programmable output voltages, the AD584
offers a unique strobe terminal which permits the device to be
turned on or off. When the AD584 is used as a power supply
reference, the supply can be switched off with a single, lowpower signal. In the “off” state the current drain by the AD584
is reduced to about 100 µA. In the “on” state the total supply
current is typically 750 µA including the output buffer amplifier.
The AD584 is recommended for use as a reference for 8-, 10- or
12-bit D/A converters which require an external precision reference. The device is also ideal for all types of A/D converters of
up to 14-bit accuracy, either successive approximation or integrating designs, and in general can offer better performance
than that provided by standard self-contained references.
The AD584J, K and L are specified for operation from 0°C to
+70°C; the AD584S and T are specified for the –55°C to
+125°C range. All grades are packaged in a hermetically sealed
eight-terminal TO-99 metal can; the AD584 J and K are also
available in an 8-pin plastic DIP.
*Protected by U.S. Patent No. 3,887,863; RE 30,586
Precision Voltage Reference
AD584*
PIN CONFIGURATIONS
8-Pin TO-99
8-Pin DIP
PRODUCT HIGHLIGHTS
1. The flexibility of the AD584 eliminates the need to designin and inventory several different voltage references. Furthermore one AD584 can serve as several references
simultaneously when buffered properly.
2. Laser trimming of both initial accuracy and temperature coefficient results in very low errors over temperature without
the use of external components. The AD584LH has a maximum deviation from 10.000 volts of ± 7.25 mV from 0°C to
+70°C.
3. The AD584 can be operated in a two-terminal “Zener”
mode at 5 volts output and above. By connecting the input
and the output, the AD584 can be used in this “Zener” configuration as a negative reference.
4. The output of the AD584 is configured to sink or source
currents. This means that small reverse currents can be tolerated in circuits using the AD584 without damage to the
reference and without disturbing the output voltage (10 V,
7.5 V and 5 V outputs).
5. The AD584 is available in versions compliant with MILSTD-883. Refer to the Analog Devices Military Products
Databook or current AD584/883B data sheet for detailed
specifications.
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
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AD584–SPECIFICATIONS
(@ VIN = +15 V and 258C)
Model AD584J AD584K AD584L
Min Typ Max Min Typ Max Min Typ Max Units
OUTPUT VOLTAGE TOLERANCE
Maximum Error
1
for Nominal
Outputs of:
10.000 V 630 610 65 mV
7.500 V 620 68 64 mV
5.000 V 615 66 63 mV
2.500 V 67.5 63.5 62.5 mV
OUTPUT VOLTAGE CHANGE
Maximum Deviation from +25°C
Value, T
MIN
to T
MAX
2
10.000 V, 7.500 V, 5.000 V Outputs 30 15 5 ppm/°C
2.500 V Output 30 15 10 ppm/°C
Differential Temperature
Coefficients Between Outputs 5 3 3 ppm/°C
QUIESCENT CURRENT 0.75 1.0 0.75 1.0 0.75 1.0 mA
Temperature Variation 1.5 1.5 1.5 µA/°C
TURN-ON SETTLING TIME TO 0.1% 200 200 200 µs
NOISE
(0.1 Hz to 10 Hz) 50 50 50 µV p-p
LONG-TERM STABILITY 25 25 25 ppm/1000 Hrs
SHORT-CIRCUIT CURRENT 30 30 30 mA
LINE REGULATION (No Load)
15 V ≤ V
(V
OUT
≤ 30 V 0.002 0.002 0.002 %/V
IN
+2.5 V) ≤ VIN ≤ 15 V 0.005 0.005 0.005 %/V
LOAD REGULATION
0 ≤ I
≤ 5 mA, All Outputs 20 50 20 50 20 50 ppm/mA
OUT
OUTPUT CURRENT
≥ V
V
IN
OUT
+2.5 V
Source @ +25°C 101010mA
Source T
Sink T
MIN
MIN
to T
to T
MAX
MAX
555mA
555mA
TEMPERATURE RANGE
Operating 0 +70 0 +70 0 +70 °C
Storage –65 +175 –65 +175 –65 +175 °C
PACKAGE OPTION
3
TO-99 (H-08A) AD584JH AD584KH AD584LH
Plastic (N-8) AD584JN AD584KN
NOTES
1
At Pin 1.
2
Calculated as average over the operating temperature range.
3
H = Hermetic Metal Can; N = Plastic DIP.
Specifications subject to change without notice.
Specifications shown in boldface are tested on all production units at final electrical
test. Results from those tests are used to calculate outgoing quality levels. All min
and max specifications are guaranteed, although only those shown in boldface are
tested on all production units.
METALIZATION PHOTOGRAPH
Dimensions shown in inches and (mm).
ABSOLUTE MAXIMUM RATINGS
Input Voltage VIN to Ground . . . . . . . . . . . . . . . . . . . . . . . 40 V
Power Dissipation
@ +25°C . . . . . . . . . . . . . . . . . . . . 600 mW
Operating Junction Temperature Range . . . .–55°C to +125°C
Lead Temperature (Soldering 10 sec) . . . . . . . . . . . . . +300°C
Thermal Resistance
Junction-to-Ambient (H-08A) . . . . . . . . . . . . . . . . 150°C/W
–2–
REV. A
Page 3
Model AD584S AD584T
Min Typ Max Min Typ Max Units
AD584
OUTPUT VOLTAGE TOLERANCE
Maximum Error
1
for Nominal
Outputs of:
10.000 V 630 610 mV
7.500 V 620 68 mV
5.000 V 615
±
6 mV
2.500 V 67.5 63.5 mV
OUTPUT VOLTAGE CHANGE
Maximum Deviation from +25°C
Value, T
MIN
to T
MAX
2
10.000 V, 7.500 V, 5.000 V Outputs 30 15 ppm/°C
2.500 V Output 30 20 ppm/°C
Differential Temperature
Coefficients Between Outputs 5 3 ppm/°C
QUIESCENT CURRENT 0.75 1.0 0.75 1.0 mA
Temperature Variation 1.5 1.5 µA/°C
TURN-ON SETTLING TIME TO 0.1% 200 200 µs
NOISE
(0.1 Hz to 10 Hz) 50 50 µV p-p
LONG-TERM STABILITY 25 25 ppm/1000 Hrs
SHORT-CIRCUIT CURRENT 30 30 mA
LINE REGULATION (No Load)
15 V ≤ V
(V
OUT
≤ 30 V 0.002 0.002 %/V
IN
+2.5 V) ≤ VIN ≤ 15 V 0.005 0.005 %/V
LOAD REGULATION
0 ≤ I
≤ 5 mA, All Outputs 20 50 20 50 ppm/mA
OUT
OUTPUT CURRENT
V
IN
≥ V
OUT
+2.5 V
Source @ +25°C1010mA
Source T
Sink T
MIN
MIN
to T
to T
MAX
MAX
55mA
55mA
TEMPERATURE RANGE
Operating –55 +125 –55 +125 °C
Storage –65 +175 –65 +175 °C
PACKAGE OPTION
TO-99 (H-08A) AD584SH AD584TH
NOTES
1
At Pin 1.
2
Calculated as average over the operating temperature range.
Specifications subject to change without notice.
Specifications shown in boldface are tested on all production units at final electrical test. Results from those tests are used to calculate outgoing quality levels. All min
and max specifications are guaranteed, although only those shown in boldface are tested on all production units.
REV. A
–3–
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AD584
APPLYING THE AD584
With power applied to Pins 8 and 4 and all other pins open, the
AD584 will produce a buffered nominal 10.0 V output between
Pins 1 and 4 (see Figure 1). The stabilized output voltage may
be reduced to 7.5 V, 5.0 V or 2.5 V by connecting the programming pins as follows:
Output
Voltage Pin Programming
7.5 V Join the 2.5 V and 5.0 V pins (2) and (3)
5.0 V Connect the 5.0 V pin (2) to the output pin (1).
2.5 V Connect the 2.5 V pin (3) to the output pin (1).
The options shown above are available without the use of any
additional components. Multiple outputs using only one
AD584, are also possible by simply buffering each voltage programming pin with a unity-gain noninverting op amp.
range will be about 20 V even for large values of R1. R2 should
not be omitted; its value should be chosen to limit the output to
a value which can be tolerated by the load circuits. If R2 is zero,
adjusting R1 to its lower limit will result in a loss of control over
the output voltage. If precision voltages are required to be set at
levels other than the standard outputs, the 20% absolute tolerance in the internal resistor ladder must be accounted for.
Alternatively, the output voltage can be raised by loading the
2.5 V tap with R3 alone. The output voltage can be lowered by
connecting R4 alone. Either of these resistors can be a fixed
resistor selected by test or an adjustable resistor. In all cases the
resistors should have a low temperature coefficient to match the
AD584 internal resistors, which have a negative T.C. less than
60 ppm/°C. If both R3 and R4 are used, these resistors should
have matched temperature coefficients.
When only small adjustments or trims are required, the circuit
of Figure 2 offers better resolution over a limited trim range.
The circuit can be programmed to 5.0 V, 7.5 V or 10 V and adjusted by means of R1 over a range of about ± 200 mV. To trim
the 2.5 V output option, R2 (Figure 2) can be reconnected to
the bandgap reference (Pin 6). In this configuration, the adjustment should be limited to ± 100 mV in order to avoid affecting
the performance of the AD584.
Figure 1. Variable Output Options
The AD584 can also be programmed over a wide range of output voltages, including voltages greater than 10 V, by the addition of one or more external resistors. Figure 1 illustrates the
general adjustment procedure, with approximate values given
for the internal resistors of the AD584. The AD584 may be
modeled as an op amp with a noninverting feedback connection,
driven by a high stability 1.215 volt bandgap reference (see Figure 3 for schematic).
When the feedback ratio is adjusted with external resistors, the
output amplifier can be made to multiply the reference voltage
by almost any convenient amount, making popular outputs of
10.24 V, 5.12 V, 2.56 V or 6.3 V easy to obtain. The most
general adjustment (which gives the greatest range and poorest
resolution) uses R1 and R2 alone (see Figure 1). As R1 is adjusted to its upper limit the 2.5 V Pin 3 will be connected to the
output, which will reduce to 2.5 V. As R1 is adjusted to its
lower limit, the output voltage will rise to a value limited by R2.
For example, if R2 is about 6 kΩ, the upper limit of the output
Figure 2. Output Trimming
Figure 3. Schematic Diagram
REV. A–4–
Page 5
AD584
PERFORMANCE OVER TEMPERATURE
Each AD584 is tested at three temperatures over the –55°C to
+125°C range to ensure that each device falls within the Maximum Error Band (see Figure 4) specified for a particular grade
(i.e., S and T grades); three-point measurement guarantees performance within the error band from 0°C to +70°C (i.e., J, K,
or L grades). The error band guaranteed for the AD584 is the
maximum deviation from the initial value at +25°C. Thus, given
the grade of the AD584, the designer can easily determine the
maximum total error from initial tolerance plus temperature
variation. For example, for the AD584T, the initial tolerance is
±l0 mV and the error band is ± 15 mV. Hence, the unit is guar-
anteed to be 10.000 volts ±25 mV from –55°C to +125°C.
Figure 4. Typical Temperature Characteristic
OUTPUT CURRENT CHARACTERISTICS
The AD584 has the capability to either source or sink current
and provide good load regulation in either direction, although it
has better characteristics in the source mode (positive current
into the load). The circuit is protected for shorts to either positive supply or ground. The output voltage vs. output current
characteristics of the device is shown in Figure 5. Source current
is displayed as negative current in the figure; sink current is
positive. Note that the short circuit current (i.e., zero volts output) is about 28 mA; when shorted to +15 volts, the sink current goes to about 20 mA.
needed, and yet respond quickly when the power is turned on
for operation. Figure 6 displays the turn-on characteristic of the
AD584. Figure 6a is generated from cold-start operation and
represents the true turn-on waveform after an extended period
with the supplies off. The figure shows both the coarse and fine
transient characteristics of the device; the total settling time to
within ±10 millivolt is about 180 µs, and there is no long ther-
mal tail appearing after the point.
Figure 6. Output Settling Characteristic
NOISE FILTERING
The bandwidth of the output amplifier in the AD584 can be reduced to filter the output noise. A capacitor ranging between
0.01 µF and 0.1 µF connected between the Cap and V
nals will further reduce the wideband and feedthrough noise in
the output of the AD584, as shown in Figure 8. However, this
will tend to increase the turn-on settling time of the device so
ample warm-up time should be allowed.
termi-
BG
Figure 5. AD584 Output Voltage vs. Sink and Source
Current
DYNAMIC PERFORMANCE
Many low power instrument manufacturers are becoming increasingly concerned with the turn-on characteristics of the
components being used in their systems. Fast turn-on components often enable the end user to keep power off when not
REV. A
Figure 7. Additional Noise Filtering with an External
Capacitor
Figure 8. Spectral Noise Density and Total rms Noise vs.
Frequency
–5–
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AD584
USING THE STROBE TERMINAL
The AD584 has a strobe input which can be used to zero the
output. This unique feature permits a variety of new applications in signal and power conditioning circuits.
Figure 9 illustrates the strobe connection. A simple NPN switch
can be used to translate a TTL logic signal into a strobe of the
output. The AD584 operates normally when there is no current
drawn from Pin 5. Bringing this terminal low, to less than
200 mV, will allow the output voltage to go to zero. In this
mode the AD584 should not be required to source or sink current (unless a 0.7 V residual output is permissible). If the
AD584 is required to sink a transient current while strobed off,
the strobe terminal input current should be limited by a 100 Ω
resistor as shown in Figure 9.
The strobe terminal will tolerate up to 5 µA leakage and its
driver should be capable of sinking 500 µA continuous. A low
leakage open collector gate can be used to drive the strobe terminal directly, provided the gate can withstand the AD584 output voltage plus one volt.
The AD584 can also use an NPN or Darlington NPN transistor
to boost its output current. Simply connect the 10 V output terminal of the AD584 to the base of the NPN booster and take
the output from the booster emitter as shown in Figure 11. The
5.0 V or 2.5 V pin must connect to the actual output in this configuration. Variable or adjustable outputs (as shown in Figures 1
and 2) may be combined with +5.0 V connection to obtain outputs above +5.0 V.
THE AD584 AS A CURRENT LIMITER
The AD584 represents an alternative to current limiter diodes
which require factory selection to achieve a desired current. Use
of current limiting diodes often results in temperature coefficients of 1%/°C. Use of the AD584 in this mode is not limited
to a set current limit; it can be programmed from 0.75 mA to
5 mA with the insertion of a single external resistor (see Figure
12). Of course, the minimum voltage required to drive the connection is 5 volts.
Figure 9. Use of the Strobe Terminal
PRECISION HIGH CURRENT SUPPLY
The AD584 can be easily connected to a power PNP or power
Darlington PNP device to provide much greater output current
capability. The circuit shown in Figure 10 delivers a precision
10 volt output with up to 4 amperes supplied to the load. The
0.1 µF capacitor is required only if the load has a significant
capacitive component. If the load is purely resistive, improved
high frequency supply rejection results from removing the
capacitor.
Figure 10. High Current Precision Supply
Figure 11. NPN Output Current Booster
Figure 12. A Two-Component Precision Current Limiter
NEGATIVE REFERENCE VOLTAGES FROM AN AD584
The AD584 can also be used in a two-terminal “Zener” mode
to provide a precision –10 volt, –7.5 volt or –5.0 volt reference.
As shown in Figure 13, the V
and V
IN
terminals are con-
OUT
nected together to the positive supply (in this case, ground).
The AD584 common pin is connected through a resistor to the
negative supply. The output is now taken from the common pin
instead of V
. With 1 mA flowing through the AD584 in this
OUT
mode, a typical unit will show a 2 mV increase in output level
over that produced in the three-terminal mode. Note also that
the effective output impedance in this connection increases from
0.2 Ω typical to 2 Ω. It is essential to arrange the output load
and the supply resistor, R
, so that the net current through the
S
AD584 is always between 1 mA and 5 mA (between 2 mA and
5 mA for operation beyond +85°C). The temperature character-
REV. A–6–
Page 7
AD584
istics and long-term stability of the device will be essentially the
same as that of a unit used in the standard three-terminal mode.
Figure 13. Two-Terminal –5 Volt Reference
The AD584 can also be used in a two-terminal mode to develop
a positive reference. V
and V
IN
are tied together and to the
OUT
positive supply through an appropriate supply resistor. The performance characteristics will be similar to those of the negative
two-terminal connection. The only advantage of this connection
over the standard three-terminal connection is that a lower primary supply can be used, as low as 0.5 volts above the desired
output voltage. This type of operation will require considerable
attention to load and primary supply regulation to be sure the
AD584 always remains within its regulating range of 1 mA to
5 mA (2 mA to 5 mA for operation beyond 85°C).
10 VOLT REFERENCE WITH MULTIPLYING CMOS D/A
OR A/D CONVERTERS
The AD584 is ideal for application with the entire AD7520
series of 10- and 12-bit multiplying CMOS D/A converters,
especially for low power applications. It is equally suitable for
the AD7574 8-bit A/D converter. In the standard hook-up as
shown in Figure 14, the standard output voltages are inverted
by the amplifier/DAC configuration to produce converted volt-
age ranges. For example, a +10 V reference produces a 0 V to
–10 V range. If an AD308 amplifier is used, total quiescent supply current will typically be 2 mA. The AD584 will normally be
used in the –10 volt mode with the AD7574 to give a 0 volt to
+10 volt ADC range. This is shown in Figure 16. Bipolar output applications and other operating details can be found in the
data sheets for the CMOS products.
Figure 14. Low Power 10-Bit CMOS DAC Application
PRECISION D/A CONVERTER REFERENCE
The AD562, like many D/A converters, is designed to operate
with a +10 volt reference element (Figure 15). In the AD562,
this 10 volt reference voltage is converted into a reference current of approximately 0.5 mA via the internal 19.95 kΩ resistor
(in series with the external 100 Ω trimmer). The gain temperature coefficient of the AD562 is primarily governed by the temperature tracking of the 19.95 kΩ resistor and the 5k/10k span
resistors; this gain T.C. is guaranteed to 3 ppm/°C. Thus, using
the AD584L (at 5 ppm/°C) as the 10 volt reference guarantees a
REV. A
Figure 15. Precision 12-Bit D/A Converter
–7–
Page 8
AD584
maximum full scale temperature coefficient of 8 ppm/°C over
the commercial range. The 10 volt reference also supplies the
normal 1 mA bipolar offset current through the 9.95k bipolar
offset resistor. The bipolar offset T.C. thus depends only on the
T.C. matching of the bipolar offset resistor to the input reference resistor and is guaranteed to 3 ppm/°C. Figure 17 demonstrates the flexibility of the AD584 applied to another popular
D/A configuration.
Figure 16. AD584 as Negative 10 Volt Reference for CMOS
ADC
C473e–10–6/86
Figure 17. Current Output 8-Bit D/A
TO-99 (H) Package
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
Plastic DIP (N) Package
PRINTED IN U.S.A.
REV. A–8–
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