Oven-Compensated, Buried Zener, 7.05 V Voltage Reference

The ADR1399 precision shunt reference features excellent temperature stability over a wide range of voltage, temperature, and quiescent current conditions. A temperature stabilizing loop is incorporated with the active Zener on a monolithic substrate, which nearly eliminates changes in voltage with temperature. The subsurface Zener circuit is fully specified at a quiescent current IREF of 3 mA and offers minimal noise (1.44 μV p-p, 0.1 Hz to 10 Hz) and excellent long-term stability (7 ppm/√kHr). The ADR1399 offers a lower output dynamic impedance (0.08 Ω) than the LM399, reducing the effects of shunt resistor (RSHUNT) and the supply voltage variation on the reference output.

Ideal applications for the ADR1399 include ultrastable digital voltmeters, precision calibration equipment, and ultrarepeatable analog-to-digital converters (ADCs). The simplicity of the basic pin configurations is shown in Figure 1. The 8-terminal LCC version offers force and sense pins for lower dynamic impedance and for Kelvin sensing.

Table 1. Related Products

Model

Output Voltage (V)

Initial Accuracy Range (mV)

ADR1399

7.05

–300 to +250

LTZ1000

7.2

–200 to +300

LM399

6.95

–200 to +350

LT1236

5 and 10

–2.5 to +2.5

Applications

* Precision voltage reference for multimeters

* Calibration equipment voltage standards

* Laboratory measurement equipment

* Industrial monitor and control instrumentation

* Ultrastable data convertors

* 7.05 V ultrastable shunt reference

* Low temperature coefficient: 0.2 ppm/℃

* Available in 4-pin TO-46 and 8-terminal LCC

* Typical reference noise for 10 Hz < f < 1 kHz: 1.84 μV rms

* Initial accuracy range: –300 mV to +250 mV