Parameter

Conditions

LM3999Z

Units

Min

Typ

Max

Initial Turn-On Current

9

≤ V

140

200

mA

Parameter

Conditions

LM199AH, LM299AH

LM399AH

Units

Min

Typ

Max

Min

Typ

Max

Reverse Breakdown Voltage

0.5 mA

≤ I

6.8

6.95

7.1

6.6

6.95

7.3

V

Reverse Breakdown Voltage

0.5 mA

≤ I

6

9

6

12

mV

Change with Current

Reverse Dynamic Impedance

I

0.5

1

0.5

1.5

Ω

Reverse Breakdown

−55˚C

≤T

LM199A

0.00002

0.00005

%/˚C

Temperature Coefficient

+85˚C

≤T

0.0005

0.0010

%/˚C

−25˚C

≤T

LM299A

0.00002

0.00005

%/˚C

0˚C

≤T

LM399A

0.00003

0.0001

%/˚C

RMS Noise

10 Hz

≤ f ≤ 10 kHz

7

20

7

50

µV

Long Term Stability

Stabilized, 22˚C

≤T

20

20

ppm

1000 Hours, I

Temperature Stabilizer

T

8.5

14

8.5

15

mA

Supply Current

T

22

28

Temperature Stabilizer

9

40

9

40

V

Supply Voltage

Warm-Up Time to 0.05%

V

3

3

sec.

Initial Turn-on Current

9

≤V

140

200

140

200

mA

Note 2: The substrate is electrically connected to the negative terminal of the temperature stabilizer. The voltage that can be applied to either terminal of the refer-

ence is 40V more positive or 0.1V more negative than the substrate.

Note 3: These specifications apply for 30V applied to the temperature stabilizer and −55˚C

0˚C

Note 4: This initial current can be reduced by adding an appropriate resistor and capacitor to the heater circuit. See the performance characteristic graphs to de-

termine values.

Note 5: Do not wash the LM199 with its polysulfone thermal shield in TCE.

Note 6: A military RETS electrical test specification is available for the LM199H/883, LM199AH/883, and LM199AH-20/883 on request.

Ordering Information

Initial

0˚C to +70˚C

−25˚C to +85˚C

−55˚C to +125˚C

NS

Tolerance

Package

2%

LM299AH

LM199AH, LM199AH/883

H04D

5%

LM399H

LM299H

H04D

LM399AH

5%

LM3999Z

Z03A

Certified Long Term Drift

The National Semiconductor LM199AH-20, LM299AH-20,

and LM399AH-50 are ultra-stable Zener references specially

selected from the production runs of LM199AH, LM299AH,

LM399AH and tested to confirm a long-term stability of 20,

20, or 50 ppm per 1000 hours, respectively. The devices are

measured every 168 hours and the voltage of each device is

logged and compared in such a way as to show the deviation

from its initial value. Each measurement is taken with a

Reference Voltage, which is derived from several groups of

NBS-traceable references such as LM199AH-20’s, 1N827’s,

and saturated standard cells, so that the deviation of any one

group will not cause false indications. Indeed, this compari-

son process has recently been automated using a specially

prepared computer program which is custom-designed to re-

ject noisy data (and require a repeat reading) and to record

the average of the best 5 of 7 readings, just as a sagacious

standards engineer will reject unbelievable readings.

The typical characteristic for the LM199AH-20 is shown be-

low. This computerized print-out form of each reference’s

stability is shipped with the unit.

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