The LM199 series are precision, temperature-stabilized
monolithic zeners offering temperature coefficients a factor
of ten better than high quality reference zeners. Constructed
on a single monolithic chip is a temperature stabilizer circuit
and an active reference zener. The active circuitry reduces
the dynamic impedance of the zener to about 0.5Ω and allows the zener to operate over 0.5 mA to 10 mA current
range with essentially no change in voltage or temperature
coefficient. Further, a new subsurface zener structure gives
low noise and excellent long term stability compared to ordinary monolithic zeners. The package is supplied with a thermal shield to minimize heater power and improve temperature regulation.
The LM199 series references are exceptionally easy to use
and free of the problems that are often experienced with ordinary zeners. There is virtually no hysteresis in reference
voltage with temperature cycling. Also, the LM199 is free of
voltage shifts due to stress on the leads. Finally, since the
unit is temperature stabilized, warm up time is fast.
The LM199 can beusedinalmost any application in place of
ordinary zeners with improved performance. Some ideal applications are analog to digital converters, calibration standards, precision voltage or current sources or precision
power supplies. Further in many cases the LM199 can replace references in existing equipment with a minimum of
wiring changes.
May 1999
The LM199 series devices are packaged in a standard hermetic TO-46 package inside a thermal shield. The LM199 is
rated for operation from −55˚C to +125˚C while the LM299 is
rated for operation from −25˚C to +85˚C and the LM399 is
rated from 0˚C to +70˚C.
The LM3999 is packaged in a standard TO-92 package and
is rated from 0˚C to +70˚C
Features
n Guaranteed 0.0001%/˚C temperature coefficient
n Low dynamic impedance — 0.5Ω
n Initial tolerance on breakdown voltage — 2
n Sharp breakdown at 400 µA
n Wide operating current — 500 µA to 10 mA
n Wide supply range for temperature stabilizer
n Guaranteed low noise
n Low power for stabilization — 300 mW at 25˚C
n Long term stability — 20 ppm
n Proven reliability, low-stress packaging in TO-46
integrated-circuit hermetic package, for low hysteresis
after thermal cycling. 33 million hours MTBF at T
+25˚C (T
n Certified long term stability available
n MIL-STD-883 compliant
Specifications for Military/Aerospace products are not
contained in this datasheet. Refer to the following Reliability Electrical Test Specifications documents:
RETS199X for LM199, RETS199AX for LM199A.
Temperature Stabilizer Voltage
LM199/LM299/LM39940V
LM399936V
Reverse Breakdown Current20 mA
Forward Current
Reference to Substrate Voltage V
Operating Temperature Range
LM199−55˚C to +125˚C
LM299−25˚C to +85˚C
LM399/LM3999−0˚C to +70˚C
Storage Temperature Range−55˚C to +150˚C
Soldering Information
TO-92 package (10 sec.)+260˚C
TO-46 package (10 sec.)+300˚C
(Note 2)40V
(RS)
−0.1V
LM199/LM299/LM3991 mA
LM3999−0.1 mA
Electrical Characteristics (Notes 3, 6)
ParameterConditionsLM199H/LM299HLM399HUnits
MinTypMaxMinTypMax
Reverse Breakdown Voltage0.5 mA ≤ I
Reverse Breakdown Voltage0.5 mA ≤ I
Change with Current
Reverse Dynamic ImpedanceI
=
R
Reverse Breakdown−55˚C≤T
Temperature Coefficient+85˚C≤T
−25˚C≤T
0˚C≤T
RMS Noise10 Hz ≤ f ≤ 10 kHz720750µV
Long Term StabilityStabilized, 22˚C≤T
1000 Hours, I
Temperature StabilizerT
Supply CurrentT
=
A
A
Temperature Stabilizer940940V
Supply Voltage
Warm-Up Time to 0.05
%
V
S
Initial Turn-on Current9≤V
Note 1: “Absolute Maximum Ratings” indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
functional, but do not guarantee specific performance limits.
≤ 10 mA6.86.957.16.66.957.3V
R
≤ 10 mA69612mV
R
1 mA0.510.51.5Ω
≤+85˚C
A
≤+125˚C0.00050.0015
A
≤85˚CLM2990.00003 0.0001
A
≤+70˚CLM3990.00003 0.0002%/˚C
A
R
25˚C, Still Air, V
=
− 55˚C2228
=
S
=
30V, T
A
=
≤40, T
+25˚C, (Note 4)140200140200mA
A
LM199
≤28˚C,2020ppm
A
=
±
%
0.1
1mA
=
30V8.5148.515mA
S
25˚C33sec.
0.00003 0.0001
%
%
%
/˚C
/˚C
/˚C
Electrical Characteristics (Note 3)
ParameterConditionsLM3999ZUnits
MinTypMax
Reverse Breakdown Voltage0.6 mA ≤ I
Reverse Breakdown Voltage0.6 mA ≤ I
Change with Current
Reverse Dynamic ImpedanceI
R
Reverse Breakdown0˚C ≤ T
Temperature Coefficient
RMS Noise10 Hz ≤ f ≤ 10 kHz7µV
Long Term StabilityStabilized, 22˚C ≤ T
1000 Hours, I
Temperature StabilizerT
A
Temperature Stabilizer36V
Supply Voltage
Warm-Up Time to 0.05
%
V
S
≤ 10 mA6.66.957.3V
R
≤ 10 mA620mV
R
=
1 mA0.62.2Ω
≤ 70˚C0.00020.0005
A
≤ 28˚C,20ppm
A
=
±
%
0.1
1mA
=
=
R
25˚C, Still Air, V
=
30V, T
25˚C5sec.
A
=
30V1218mA
S
www.national.com3
%
/˚C
Page 4
Electrical Characteristics (Note 3) (Continued)
ParameterConditionsLM3999ZUnits
MinTypMax
Initial Turn-On Current9 ≤ V
S
≤ 40, T
=
25˚C140200mA
A
Electrical Characteristics (Notes 3, 6)
ParameterConditionsLM199AH, LM299AHLM399AHUnits
MinTypMaxMinTypMax
Reverse Breakdown Voltage0.5 mA ≤ I
Reverse Breakdown Voltage0.5 mA ≤ I
Change with Current
Reverse Dynamic ImpedanceI
=
R
Reverse Breakdown−55˚C≤T
Temperature Coefficient+85˚C≤T
−25˚C≤T
0˚C≤T
RMS Noise10 Hz ≤ f ≤ 10 kHz720750µV
Long Term StabilityStabilized, 22˚C≤T
1000 Hours, I
Temperature StabilizerT
Supply CurrentT
=
A
A
Temperature Stabilizer940940V
Supply Voltage
Warm-Up Time to 0.05
%
V
S
Initial Turn-on Current9≤V
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 reference 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≤T
≤+70˚C for the LM399 and LM3999.
0˚C≤T
A
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 determine 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.
≤ 10 mA6.86.957.16.66.957.3V
R
≤ 10 mA69612mV
R
1 mA0.510.51.5Ω
≤+85˚C
A
≤+125˚C0.00050.0010
A
≤85˚CLM299A0.00002 0.00005
A
≤+70˚CLM399A0.00003 0.0001%/˚C
A
R
25˚C, Still Air, V
=
− 55˚C2228
=
S
=
30V, T
A
=
≤40, T
+25˚C, (Note 4)140200140200mA
A
LM199A
≤28˚C,2020ppm
A
=
±
%
0.1
1mA
=
30V8.5148.515mA
S
25˚C33sec.
0.00002 0.00005
≤+125˚C for the LM199; −25˚C≤TA≤+85˚C for the LM299 and
A
%
%
%
/˚C
/˚C
/˚C
Ordering Information
Initial0˚C to +70˚C−25˚C to +85˚C−55˚C to +125˚CNS
TolerancePackage
%
2
%
5
LM399HLM299HH04D
LM399AH
%
5
LM3999ZZ03A
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
probable-worst-case deviation of
Reference Voltage, which is derived from several groups of
NBS-traceable references such as LM199AH-20’s, 1N827’s,
www.national.com4
±
2 ppm, compared to the
LM299AHLM199AH, LM199AH/883H04D
and saturated standard cells, so that the deviation of any one
group will not cause false indications. Indeed, this comparison process has recently been automated using a specially
prepared computer program which is custom-designed to reject 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 below. This computerized print-out form of each reference’s
stability is shipped with the unit.
Page 5
Typical Characteristics
National Semiconductor
Certified Long Term Drift
HrsDrift
168−20
336−24
504−36
672−34
840−40
1008−36
Testing Conditions
Heater Voltage: 30V
Zener Current: 1 mA
Ambient Temp.: 25˚C
Typical Performance Characteristics
DS005717-12
Reverse Characteristics
Zener Noise Voltage
DS005717-19
DS005717-22
Reverse Voltage Change
Stabilization Time
DS005717-20
DS005717-23
Dynamic Impedance
DS005717-21
Heater Current
DS005717-24
www.national.com5
Page 6
Typical Performance Characteristics (Continued)
Initial Heater Current
DS005717-25
Low Frequency Noise Voltage
Heater Current (To Limit This
Surge, See Next Graph)
DS005717-26
Response Time
Heater Surge Limit Resistor vs
Minimum Supply Voltage at Various
Minimum Temperatures
*Heater must be bypassed witha2µForlarger
tantalum capacitor if resistors are used.
DS005717-27
DS005717-3
Typical Applications
Single Supply Operation
DS005717-28
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DS005717-7
Split Supply Operation
DS005717-29
Page 7
Typical Applications (Continued)
Negative Heater Supply with
Positive Reference
DS005717-30
Buffered Reference
With Single Sypply
DS005717-31
Positive Current Source
Standard Cell Replacement
DS005717-32
DS005717-33
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Page 8
Typical Applications (Continued)
Negative Current Source
DS005717-34
Square Wave Voltage Reference
14V Reference
DS005717-35
Portable Calibrator*
*Warm-up time 10 seconds; intermittent operation does not degrade long
term stability.
Precision Clamp*
DS005717-36
DS005717-37
www.national.com8
*Clamp will sink 5 mA when input goes more positive than reference
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and
whose failure to perform when properly used in
accordance with instructions for use provided in the
2. A critical component is any component of a life
support device or system whose failure to perform
can be reasonably expected to cause the failure of
the life support device or system, or to affect its
safety or effectiveness.
labeling, can be reasonably expected to result in a
significant injury to the user.
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.