Data Sheet

AD1582/AD1583/AD1584/AD1585

Rev. J | Page 11 of 16

APPLICATIONS INFORMATION

The AD1582/AD1583/AD1584/AD1585 are series references

that can be used for many applications. To achieve optimum

performance with these references, only two external compo-

nents are required. Figure 10 shows the AD1582/AD1583/

AD1584/AD1585 configured for operation under all loading

conditions. With a simple 4.7 µF capacitor attached to the input

and a 1 µF capacitor applied to the output, the devices can achieve

specified performance for all input voltage and output current

requirements. For best transient response, add a 0.1 µF capacitor

in parallel with the 4.7 µF capacitor. While a 1 µF output capacitor

can provide stable performance for all loading conditions, the

AD1582/AD1583/AD1584/AD1585 can operate under low

0.2 µF output capacitor. The 4.7 µF capacitor on the input can

be reduced to 1 μF in this condition.

Unlike conventional shunt reference designs, the AD1582/

AD1583/AD1584/AD1585 provide stable output voltages at

constant operating current levels. When properly decoupled,

as shown in Figure 10, these devices can be applied to any

circuit and provide superior low power solutions.

1

2

3

AD1582/

AD1583/

AD1584/

AD1585

1µF

4.7µF

+

–

Figure 10. Typical Connection Diagram

TEMPERATURE PERFORMANCE

The AD1582/AD1583/AD1584/AD1585 are designed for

applications where temperature performance is important.

Extensive temperature testing and characterization ensure

that device performance is maintained over the specified

temperature range.

The error band guaranteed with the AD1582/AD1583/AD1584/

AD1585 is the maximum deviation from the initial value at 25°C.

Therefore, for a given grade of the AD1582/AD1583/AD1584/

AD1585, the designer can easily determine the maximum total

error by summing initial accuracy and temperature variation. For

the temperature error band is ±8 mV; therefore, the reference is

guaranteed to be 2.5 V ± 10 mV from −40°C to +125°C.

Figure 11 shows the typical output voltage drift for the AD1582/

AD1583/AD1584/AD1585 and illustrates the methodology. The

box in Figure 11 is bounded on the x-axis by operating tempera-

ture extremes. It is bounded on the y-axis by the maximum

and minimum output voltages observed over the operating

temperature range. The slope of the diagonal drawn from the

initial output value at 25°C to the output values at +125°C and

−40°C determines the performance grade of the device.

Duplication of these results requires a test system that is highly

accurate with stable temperature control. Evaluation of the

AD1582/AD1583/AD1584/AD1585 produces curves similar

to those in Figure 5 and Figure 11, but output readings can vary

depending on the test methods and test equipment used.

2.504

2.502

2.500

2.498

2.496

2.494

2.492

TEMPERATURE (°C)

–40

–20

0

20

40

60

80

100

120

2.504

2.502

2.500

2.498

2.496

2.494

2.492

TEMPERATURE (°C)

–40

–20

0

20

40

60

80

100

120

Figure 11. Output Voltage vs. Temperature

VOLTAGE OUTPUT NONLINEARITY VS.

TEMPERATURE

When using a voltage reference with data converters, it is

important to understand the impact that temperature drift can

have on converter performance. The nonlinearity of the reference

output drift represents additional error that cannot be easily

calibrated out of the overall system. To better understand the

impact such a drift can have on a data converter, refer to Figure 12,

where the measured drift characteristic is normalized to the

endpoint average drift. The residual drift error for the AD1582/

AD1583/AD1584/AD1585 of approximately 200 ppm demon-

strates that these parts are compatible with systems that require

12-bit accurate temperature performance.

250

200

150

100

50

0

–50

TEMPERATURE (°C)

–50

–25

0

25

50

75

100

Figure 12. Residual Drift Error