NSC 5962-8992101XA Datasheet

LM129/LM329
Precision Reference

General Description

The LM129 and LM329 family are precision multi-current
temperature-compensated 6.9V zener references with dy­namic impedances a factor of 10 to 100 less than discrete di­odes. Constructed in a single silicon chip, the LM129 uses
active circuitry to buffer the internal zener allowing the de­vice to operate over a 0.5 mA to 15 mA range with virtually
no change in performance. The LM129 and LM329 are avail­able with selected temperature coefficients of 0.001, 0.002,

0.005 and 0.01%/˚C. These references also have excellent
long term stability and low noise.

Anewsubsurfacebreakdownzener used in the LM129 gives
lower noise and better long-term stability than conventional
IC zeners. Further the zener and temperature compensating
transistor are made by a planar process so they are immune
to problems that plague ordinary zeners. For example, there
is virtually no voltage shift in zener voltage due to tempera­ture cycling and the device is insensitive to stress on the
leads.

The LM129 can be used in place of conventional zeners with
improved performance. The low dynamic impedance simpli­fies biasing and the wide operating current allows the re­placement of many zener types.

The LM129 is packaged in a 2-lead TO-46 package and is
rated for operation over a −55˚C to +125˚C temperature
range. The LM329 for operation over 0˚C to 70˚C is available
in both a hermetic TO-46 package and a TO-92 epoxy pack­age.

Features

n 0.6 mA to 15 mA operating current
n 0.6Ω dynamic impedance at any current
n Available with temperature coefficients of 0.001%/˚C
n 7µV wideband noise
n 5% initial tolerance
n 0.002% long term stability
n Low cost
n Subsurface zener

Connection Diagrams

Metal Can Package (T0–46)

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Pin 2 is electrically connected to case

Bottom View

Order Number LM129AH, LM129AH/883, LM129BH,

LM129BH/883, LM129CH, LM329AH, LM329BH,

LM329CH or LM329DH
See NS Package H02A

Plastic Package (TO-92)

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Bottom View

Order Number LM329BZ,

LM329CZ or LM329DZ
See NS Package Z03A

March 2000

LM129/LM329 Precision Reference

© 2000 National Semiconductor Corporation DS005714 www.national.com

Typical Applications

Simple Reference

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LM129/LM329

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Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.

(Note 3)
Reverse Breakdown Current 30 mA

Forward Current 2 mA

Operating Temperature Range

LM129 −55˚C to +125˚C

LM329 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

Electrical Characteristics (Note 2)

LM129A, B, C LM329A, B, C, D

Parameter Conditions Units

Min Typ Max Min Typ Max

Reverse Breakdown Voltage T

A

= 25˚C,

0.6 mA ≤ I

R

≤ 15 mA 6.7 6.9 7.2 6.6 6.9 7.25 V

Reverse Breakdown Change T

A

= 25˚C,

with Current (Note 4) 0.6 mA ≤ I

R

≤ 15 mA 9 14 9 20 mV

Reverse Dynamic Impedance T

A

= 25˚C, IR= 1 mA 0.6 1 0.8 2 Ω
(Note 4)
RMS Noise T

A

= 25˚C,

10 Hz ≤ F ≤ 10 kHz 7 20 7 100 µV

Long Term Stability T

A

= 45˚C±0.1˚C,
(1000 hours) I

R

=1mA±0.3% 20 20 ppm

Temperature Coefficient I

R

=1mA
LM129A, LM329A 6 10 6 10 ppm/˚C
LM129B, LM329B 15 20 15 20 ppm/˚C
LM129C, LM329C 30 50 30 50 ppm/˚C
LM329D 50 100 ppm/˚C

Change In Reverse Breakdown 1 mA ≤ I

R

≤ 15 mA 1 1 ppm/˚C

Temperature Coefficient

Reverse Breakdown Change 1 mA ≤ I

R

≤ 15 mA 12 12 mV

with Current

Reverse Dynamic Impedance 1 mA ≤ I

R

≤ 15 mA 0.8 1 Ω

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.

Note 2: These specifications apply for −55˚C ≤ T

A

≤ +125˚C for the LM129 and 0˚C ≤ TA≤ +70˚C for the LM329 unless otherwise specified. The maximum junction
temperature for an LM129 is 150˚C and LM329 is 100˚C. For operating at elevated temperature, devices in TO-46 package must be derated based on a thermal re­sistance of 440˚C/W junction to ambient or 80˚C/W junction to case. For the TO-92 package, the derating is based on 180˚C/W junction to ambient with 0.4" leads
from a PC board and 160˚C/W junction to ambient with 0.125" lead length to a PC board.

Note 3: Refer to RETS129H for LM129 family military specifications.
Note 4: These changes are tested on a pulsed basis with a low duty-cycle. For changes versus temperature, compute in terms of tempco.

LM129/LM329

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