Laser Trimmed to High Accuracy:
10.000 Volts ؎5 mV (L and U)
Trimmed Temperature Coefficient:
5 ppm/؇C max, 0؇C to +70؇C (L)
10 ppm/؇C max, –55؇C to +125؇C (U)
Excellent Long-Term Stability:
25 ppm/1000 hrs. (Noncumulative)
Negative 10 Volt Reference Capability
Low Quiescent Current: 1.0 mA max
10 mA Current Output Capability
3-Terminal TO-5 Package
MIL-STD-883 Compliant Versions Available
10 V IC Reference
FUNCTIONAL BLOCK DIAGRAM
The AD581 is a three-terminal, temperature compensated,
monolithic bandgap voltage reference which provides a precise
10.00 volt output from an unregulated input level from 12 to 30
volts. Laser Wafer Trimming (LWT) is used to trim both the
initial error at +25°C as well as the temperature coefficient,
which results in high precision performance previously available
only in expensive hybrids or oven-regulated modules. The 5 mV
initial error tolerance and 5 ppm/°C guaranteed temperature co-
efficient of the AD581L represent the best performance combi-
nation available in a monolithic voltage reference.
The bandgap circuit design used in the AD581 offers several ad-
vantages over classical Zener breakdown diode techniques. Most
important, no external components are required to achieve full
accuracy and stability of significance to low power systems. In
addition, total supply current to the device, including the output
buffer amplifier (which can supply up to 10 mA) is typically
750 µA. The long-term stability of the bandgap design is equiva-
lent or superior to selected Zener reference diodes.
The AD581 is recommended for use as a reference for 8-, 10- or
12-bit D/A converters which require an external precision refer-
ence. The device is also ideal for all types of A/D converters up
to 14-bit accuracy, either successive approximation or integrat-
ing designs, and in general can offer better performance than
that provided by standard self-contained references.
The AD581J, K, and L are specified for operation from 0°C to
+70°C; the AD581S, T, and U are specified for the –55°C to
+125°C range. All grades are packaged in a hermetically sealed
three-terminal TO-5 metal can.
1. Laser trimming of both initial accuracy and temperature
coefficient results in very low errors over temperature
without the use of external components. The AD581L
has a maximum deviation from 10.000 volts of ±7.25 mV
from 0°C to +70°C, while the AD581U guarantees
± 15 mV maximum total error without external trims
from –55°C to +125°C.
2. Since the laser trimming is done on the wafer prior to sepa-
ration into individual chips, the AD581 will be extremely
valuable to hybrid designers for its ease of use, lack of
required external trims, and inherent high performance.
3. The AD581 can also be operated in a two-terminal
“Zener” mode to provide a precision negative 10 volt
reference with just one external resistor to the unregu-
lated supply. The performance in this mode is nearly equal
to that of the standard three-terminal configuration.
4. Advanced circuit design using the bandgap concept
allows the AD581 to give full performance with an un-
regulated input voltage down to 13 volts. With an exter-
nal resistor, the device will operate with a supply as low
as 11.4 volts.
5. The AD581 is available in versions compliant with MIL-
STD-883. Refer to the Analog Devices Military Prod-
ucts Databook or current AD581/883B data sheet for
*Covered by Patent Nos. 3,887,863; RE 30,586.
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.
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