Datasheet LM4050CIM3X-5.0, LM4050CIM3X-4.1, LM4050CIM3X-2.5, LM4050CIM3-8.2, LM4050CIM3-5.0 Datasheet (NSC)

LM4050
Precision Micropower Shunt Voltage Reference

LM4050 Precision Micropower Shunt Voltage Reference

May 2000

General Description

Ideal for space critical applications, the LM4050 precision
voltage reference is available in the sub-miniature (3 mm x

1.3 mm) SSOT-23 surface-mount package. The LM4050’s
design eliminates theneed for an external stabilizing capaci­tor while ensuring stability with any capacitive load, thus
making the LM4050 easy to use. Further reducing design ef­fort is the availability of several fixed reverse breakdownvolt­ages: 2.500V, 4.096V, 5.000V, 8.192V, and 10.000V. The
minimum operating current increases from 60 µA for the
LM4050-2.5 to 100 µA for the LM4050-10.0. All versions
have a maximum operating current of 15 mA.

The LM4050 utilizes fuse and zener-zap reverse breakdown
voltage trim during wafer sort to ensure that the prime parts
have an accuracy of better than
Bandgap reference temperature drift curvature correction
and low dynamic impedance ensure stable reverse break­down voltage accuracy over a wide range of operating tem­peratures and currents.

All grades and voltage options of the LM4050 operate be­tween −40˚C and +85˚C. Selected parts can operate in the
extended temperature range, from −40˚C and +125˚C.

±

0.1% (A grade) at 25˚C.

Features

n Small packages: SSOT-23
n No output capacitor required
n Tolerates capacitive loads
n Fixed reverse breakdown voltages of 2.500V, 4.096V,

5.000V, 8.192V, and 10.000V

Key Specifications (LM4050-2.5)

n Output voltage tolerance

±

(A grade, 25˚C)

n Low output noise

(10 Hz to 10 kHz) 41 µV

n Wide operating current range 60 µA to 15 mA
n Industrial temperature range −40˚C to +85˚C
n Extended temperature range −40˚C to +125˚C
n Low temperature coefficient 50 ppm/˚C (max)

0.1% (max)

(typ)

rms

Applications

n Portable, Battery-Powered Equipment
n Data Acquisition Systems
n Instrumentation
n Process Control
n Energy Management
n Product Testing
n Automotive
n Precision Audio Components

Connection Diagrams

SSOT-23

DS101045-1

*This pin must be left floating or connected to pin 2.

Top View

See NS Package Number MF03A

© 2000 National Semiconductor Corporation DS101045 www.national.com

Ordering Information

LM4050

Industrial Temperature Range (−40 ˚C to +85 ˚C)

Reverse Breakdown

Voltage Tolerance at 25˚C and Average

Reverse Breakdown

Voltage Temperature Coefficient

±

0.1%, 50 ppm/˚C max (A grade)

±

0.2%, 50 ppm/˚C max (B grade)

±

0.5%, 50 ppm/˚C max (C grade)

LM4050 Supplied as 1000 Units,

Tape and Reel

LM4050AIM3-2.5 LM4050AIM3X-2.5
LM4050AIM3-4.1 LM4050AIM3X-4.1
LM4050AIM3-5.0 LM4050AIM3X-5.0
LM4050AIM3-8.2 LM4050AIM3X-8.2

LM4050AIM3-10 LM4050AIM3X-10
LM4050BIM3-2.5 LM4050BIM3X-2.5
LM4050BIM3-4.1 LM4050BIM3X-4.1
LM4050BIM3-5.0 LM4050BIM3X-5.0
LM4050BIM3-8.2 LM4050BIM3X-8.2

LM4050BIM3-10 LM4050BIM3X-10
LM4050CIM3-2.5 LM4050CIM3X-2.5
LM4050CIM3-4.1 LM4050CIM3X-4.1
LM4050CIM3-5.0 LM4050CIM3X-5.0
LM4050CIM3-8.2 LM4050CIM3X-8.2

LM4050CIM3-10 LM4050CIM3X-10

LM4050 Supplied as 3000 Units,

Tape and Reel

Extended Temperature Range (−40 ˚C to +125 ˚C)

Reverse Breakdown

Voltage Tolerance at 25˚C and Average

Reverse Breakdown

Voltage Temperature Coefficient

±

0.5%, 50 ppm/˚C max (C grade) LM4050CEM3-2.5 LM4050CEM3X-2.5

LM4050 Supplied as 1000 Units,

Tape and Reel

LM4050 Supplied as 3000 Units,

Tape and Reel

SSOT-23 Package Marking Information

Only three fields of marking are possible on the SSOT-23’s small surface. This table gives the meaning of the three fields.

Part Marking Field Definition

RCA First Field:
RDA R = Reference
REA Second Field:
RFA C = 2.500V Voltage Option
RGA D = 4.096V Voltage Option
RCB E = 5.000V Voltage Option
RDB F = 8.192V Voltage Option
REB G = 10.000V Voltage Option
RFB
RGB Third Field:
RCC A–C = Initial Reverse Breakdown Voltage or Reference Voltage Tolerance
RDC A =
REC
RFC
RGC

www.national.com 2

±

0.1%, B =±0.2%, C = +0.5%,

LM4050

Absolute Maximum Ratings (Note 1)

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

Reverse Current 20 mA
Forward Current 10 mA

Power Dissipation (T

= 25˚C) (Note 3)

A

M3 Package 280 mW
Storage Temperature (Note 2) −65˚C to +150˚C
Lead Temperature
M3 Package

Vapor phase (60 seconds) +215˚C
Infrared (15 seconds) +220˚C

ESD Susceptibility

Human Body Model (Note 4) 2 kV

See AN-450 “Surface Mounting Methods and Their Effect
on Product Reliability” for other methods of soldering
surface mount devices.

Operating Ratings(Notes 1, 3)

Temperature Range (T

Reverse Current

LM4050-2.5
Electrical Characteristics

Boldface limits apply for TA=TJ=T

verse Breakdown Voltage tolerances of

Symbol Parameter Conditions Typical

V

Reverse Breakdown

R

Voltage
Reverse Breakdown

Voltage Tolerance (Note 7)

I

RMIN

∆V

Minimum Operating Current 41 µA

/∆T Average Reverse

R

Breakdown Voltage
Temperature Coefficient
(Note 7)

∆V

/∆IRReverse Breakdown

R

Voltage Change with
Operating Current Change
(Note 8)

Z

Reverse Dynamic

R

Impedance

e

∆V

Wideband Noise IR= 100 µA 41 µV

N

Reverse Breakdown

R

Voltage Long Term Stability

V

Output Hysteresis ∆T = −40˚C to 125˚C 0.7 mV

HYST

to T

MIN

±

0.1%,±0.2%, and 0.5% respectively.

; all other limits TA=TJ= 25˚C. The grades A, B and C designate initial Re-

MAX

(Note 5)

IR= 100 µA 2.500 V

I

= 100 µA

R

Industrial Temp. Range
Devices

Extended Temp. Range
Devices

=10mA

I

R

I

=1mA

R

I

= 100 µA

R

≤ IR≤ 1 mA 0.3 mV

I

RMIN

1mA≤I

≤15 mA 2.3 mV

R

IR= 1 mA, f = 120 Hz,

= 0.1 I

I

AC

R

±

20 ppm/˚C

±

15 ppm/˚C

±

15

0.3 Ω

10 Hz ≤ f ≤ 10 kHz
t = 1000 hrs

T = 25˚C

= 100 µA

I

R

±

0.1˚C

120 ppm

Machine Model (Note 4) 200V

≤ TA≤ T

min

Industrial Temperature Range −40˚C ≤ T
Extended temperature Range −40˚C ≤ T

≤ +85˚C

A

≤ +125˚C

A

max

LM4050-2.5 60 µA to 15 mA
LM4050-4.1 68 µA to 15 mA
LM4050-5.0 74 µA to 15 mA
LM4050-8.2 91 µA to 15 mA
LM4050-10.0 100 µA to 15 mA

LM4050AIM3

Limits

(Note 6)

LM4050BIM3

Limits

(Note 6)

LM4050CIM3

LM4050CEM3

Limits

Units

(Limit)

(Note 6)

±

2.5

±

11

±

5.0

±

14

±

13 mV (max)

±

21 mV (max)

±

25 mV (max)

60 60 60 µA (max)

65 65 65 µA (max)

±

50

±

50

±

50 ppm/˚C (max)

0.8 0.8 0.8 mV (max)

1.2 1.2 1.2 mV (max)

6.0 6.0 6.0 mV (max)

8.0 8.0 8.0 mV (max)

rms

)

www.national.com3

LM4050-4.1
Electrical Characteristics (Industrial Temperature Range)

LM4050

Boldface limits apply for TA=TJ=T

verse Breakdown Voltage tolerances of

to T

MIN

±

0.1%,±0.2%, and 0.5% respectively.

; all other limits TA=TJ= 25˚C. The grades A, B and C designate initial Re-

MAX

Symbol Parameter Conditions

V

Reverse Breakdown

R

IR= 100 µA 4.096 V

Voltage
Reverse Breakdown

I

= 100 µA

R

Voltage Tolerance (Note 7)

I

RMIN

∆V

∆V

Minimum Operating Current 52 µA

/∆T Average Reverse

R

Breakdown Voltage
Temperature
Coefficient(Note 7)

/∆IRReverse Breakdown

R

=10mA

I

R

I

=1mA

R

I

= 100 µA

R

≤ IR≤ 1 mA 0.2 mV

I

RMIN

Voltage Change with
Operating Current Change
(Note 8)

Z

Reverse Dynamic

R

Impedance

e

Wideband Noise IR= 100 µA 93 µV

N

1mA≤I

≤15 mA 2.0 mV

R

IR= 1 mA, f = 120 Hz, 0.5 Ω
I

= 0.1 I

AC

R

10 Hz ≤ f ≤ 10 kHz

∆V

V

Reverse Breakdown

R

Voltage Long Term Stability

Output Hysteresis ∆T = −40˚C to 125˚C 1.148 mV

HYST

t = 1000 hrs
T = 25˚C
I

R

±

= 100 µA

0.1˚C

Typical

LM4050AIM3 LM4050BIM3 LM4050CIM3

(Note 5)

Limits Limits Limits

(Note 6) (Note 6) (Note 6)

±

4.1

±

18

±

8.2

±

22

±

21 mV (max)

±

34 mV (max)

68 68 68 µA (max)
73 73 73 µA (max)

±

30 ppm/˚C

±

20 ppm/˚C

±

20

±

50

±

50

±

50 ppm/˚C (max)

0.9 0.9 0.9 mV (max)

1.2 1.2 1.2 mV (max)

7.0 7.0 7.0 mV (max)

10.0 10.0 10.0 mV (max)

120 ppm

Units

(Limit)

rms

www.national.com 4

LM4050-5.0
Electrical Characteristics (Industrial Temperature Range)

Boldface limits apply for TA=TJ=T

verse Breakdown Voltage tolerances of

to T

MIN

±

0.1%,±0.2% and 0.5% respectively.

; all other limits TA=TJ= 25˚C. The grades A, B and C designate initial Re-

MAX

LM4050

Symbol Parameter Conditions

V

Reverse Breakdown

R

IR= 100 µA 5.000 V

Voltage
Reverse Breakdown

I

= 100 µA

R

Voltage Tolerance (Note 7)

I

∆V

∆V

Minimum Operating Current 56 µA

RMIN

/∆T Average Reverse

R

Breakdown Voltage
Temperature Coefficient
(Note 7)

/∆IRReverse Breakdown

R

=10mA

I

R

I

=1mA

R

I

= 100 µA

R

≤ IR≤ 1 mA 0.2 mV

I

RMIN

Voltage Change with
Operating Current Change
(Note 8)

1mA≤I

Z

e

Reverse Dynamic

R

Impedance
Wideband Noise IR= 100 µA 93 µV

N

IR= 1 mA, f = 120 Hz, 0.5 Ω
I

AC

≤15 mA 2.0 mV

R

= 0.1 I

R

10 Hz ≤ f ≤ 10 kHz

∆V

V

Reverse Breakdown

R

Voltage Long Term Stability

Output Hysteresis ∆T = −40˚C to 125˚C 1.4 mV

HYST

t = 1000 hrs
T = 25˚C
I

R

±

= 100 µA

0.1˚C 120 ppm

Typical

(Note 5)

Limits

Limits Limits

(Note 6) (Note 6) (Note 6)

LM4050AIM3 LM4050BIM3 LM4050CIM3

±

5.0

±

22

±

10

±

27

±

25 mV (max)

±

42 mV (max)

74 74 74 µA (max)
80 80 80 µA (max)

±

30 ppm/˚C

±

20 ppm/˚C

±

20

±

50

±

50

±

50 ppm/˚C (max)

1.0 1.0 1.0 mV (max)

1.4 1.4 1.4 mV (max)

8.0 8.0 8.0 mV (max)

12.0 12.0 12.0 mV (max)

Units

(Limit)

Ω (max)

rms

www.national.com5

LM4050-8.2
Electrical Characteristics (Industrial Temperature Range)

LM4050

Boldface limits apply for TA=TJ=T

verse Breakdown Voltage tolerances of

to T

MIN

±

0.1% and±0.2% and 0.5% respectively.

; all other limits TA=TJ= 25˚C. The grades A, B and C designate initial Re-

MAX

Symbol Parameter Conditions

V

Reverse Breakdown

R

IR= 150 µA 8.192 V

Voltage
Reverse Breakdown

I

= 150 µA

R

Voltage Tolerance (Note 7)

I

RMIN

∆V

∆V

Minimum Operating Current 74 µA

/∆T Average Reverse

R

Breakdown Voltage
Temperature
Coefficient(Note 7)

/∆IRReverse Breakdown

R

=10mA

I

R

I

=1mA

R

I

= 150 µA

R

≤ IR≤ 1 mA 0.6 mV

I

RMIN

Voltage Change with
Operating Current Change
(Note 8)

1mA≤I

Z

e

Reverse Dynamic

R

Impedance
Wideband Noise IR= 150 µA 150 µV

N

IR= 1 mA, f = 120 Hz, 0.6 Ω
I

AC

≤15 mA 7.0 mV

R

= 0.1 I

R

10 Hz ≤ f ≤ 10 kHz

∆V

V

Reverse Breakdown

R

Voltage Long Term Stability

Output Hysteresis ∆T = −40˚C to 125˚C 2.3 mV

HYST

t = 1000 hrs
T = 25˚C
I

R

±

= 150 µA

0.1˚C 120 ppm

Typical

LM4050AIM3 LM4050BIM3 LM4050CIM3

(Note 5)

Limits Limits Limits

(Note 6) (Note 6) (Note 6)

±

8.2

±

35

±

16

±

43

±

41 mV (max)

±

68 mV (max)

91 91 91 µA (max)
95 95 95 µA (max)

±

40 ppm/˚C

±

20 ppm/˚C

±

20

±

50

±

50

±

50 ppm/˚C

1.3 1.3 1.3 mV (max)

2.5 2.5 2.5 mV (max)

10.0 10.0 10.0 mV (max)

18.0 18.0 18.0 mV (max)

Units

(Limit)

(max)

rms

www.national.com 6

LM4050-10.0
Electrical Characteristics (Industrial Temperature Range)

Boldface limits apply for TA=TJ=T

verse Breakdown Voltage tolerances of

to T

MIN

±

0.1% and±0.2% and 0.5% respectively.

; all other limits TA=TJ= 25˚C. The grades A, B and C designate initial Re-

MAX

LM4050

Symbol Parameter Conditions

Typical

(Note 5)

Limits Limits Limits

(Note 6) (Note 6) (Note 6)

LM4050AIM3 LM4050BIM3 LM4050CIM3

V

Reverse Breakdown

R

IR= 150 µA 10.00 V

Voltage

I

RMIN

Reverse Breakdown
Voltage Tolerance (Note 7)

I

= 150 µA

R

±

10

±

43

Minimum Operating Current 80 µA

±

20

±

53

±

50 mV (max)

±

83 mV (max)

100 100 100 µA (max)
103 103 103 µA (max)

∆V

/∆T Average Reverse

R

Breakdown Voltage
Temperature Coefficient
(Note 7)

∆V

/∆IRReverse Breakdown

R

Voltage Change with
Operating Current Change
(Note 8)

=10mA

I

R

I

=1mA

R

I

= 150 µA

R

≤ IR≤ 1 mA 0.8 mV

I

RMIN

1mA≤I

≤15 mA 8.0 mV

R

±

40 ppm/˚C

±

20 ppm/˚C

±

20

±

50

±

50

±

50 ppm/˚C

1.5 1.5 1.5 mV (max)

3.5 3.5 3.5 mV (max)

12.0 12.0 12.0 mV (max)

23.0 23.0 23.0 mV (max)

Z

e

Reverse Dynamic

R

Impedance
Wideband Noise IR= 150 µA 150 µV

N

IR= 1 mA, f = 120 Hz, 0.7 Ω
I

= 0.1 I

AC

R

10 Hz ≤ f ≤ 10 kHz

∆V

V

Reverse Breakdown

R

Voltage Long Term Stability

Output Hysteresis ∆T = −40˚C to 125˚C 2.8 mV

HYST

Note 1: AbsoluteMaximumRatingsindicatelimitsbeyondwhichdamageto the device may occur.OperatingRatingsindicateconditionsforwhich the device is func­tional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The guaranteed speci­fications apply only for the test conditions listed. Some performance characteristics may degrade when the device is not operated under the listed test conditions.

Note 2: If parts are exposed to temperatures outside the specific operating temperature range, the output may shift due to hysteresis.
Note 3: The maximum power dissipation must be derated at elevated temperatures and is dictated by T

bient thermal resistance), and T
given in the Absolute Maximum Ratings, whichever is lower. For the LM4050, T
326˚C/W for the SSOT-23 package.

Note 4: The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. The machine model is a 200 pF capacitor discharged di-
rectly into each pin.

Note 5: Typicals are at T
Note 6: Limitsare100%production tested at 25˚C. Limits over temperature are guaranteed through correlation using Statistical Quality Control (SQC) methods. The

limits are used to calculate National’s AOQL.
Note 7: Theboldface (over-temperature) limit for Reverse Breakdown VoltageTolerance is defined as the room temperature Reverse Breakdown Voltage Tolerance

±

[(∆VR/∆T)(max∆T)(VR)]. Where, ∆VR/∆T is the VRtemperature coefficient, max∆T is the maximum difference in temperature from the reference point of 25˚C to T

MIN or T

= 65˚C is shown below:

, and VRis the reverse breakdown voltage. The total over-temperature tolerance for the different grades in the industrial temperature range where max∆T

MAX

(ambient temperature). The maximum allowable power dissipation at any temperature is PD

A

= 25˚C and represent most likely parametric norm.

J

t = 1000 hrs
T = 25˚C
I

R

±

= 150 µA

0.1˚C 120 ppm

(maximum junction temperature), θJA(junction to am-

Jmax

= 125˚C, and the typical thermal resistance (θJA), when board mounted, is

Jmax

max

=(T

Jmax−TA

)/θJAor the number

A-grade:±0.425% =±0.1%±50 ppm/˚C x 65˚C
B-grade:
C-grade:

Therefore, as an example, the A-grade LM4050-2.5 has an over-temperature Reverse Breakdown Voltage tolerance of±2.5V x 0.425% =±11 mV.
Note 8: Load regulation is measured on pulse basis from no load to the specified load current. Output changes due to die temperature change must be taken into

account separately.

±

0.525% =±0.2%±50 ppm/˚C x 65˚C

±

0.825% =±0.5%±50 ppm/˚C x 65˚C

Units

(Limit)

(max)

rms

www.national.com7

Typical Performance Characteristics

LM4050

Output Impedance vs Frequency

Output Impedance vs Frequency

Reverse Characteristics and
Minimum Operating Current

Thermal Hysteresis

DS101045-10

DS101045-12

DS101045-11

Noise Voltage vs Frequency

DS101045-13

DS101045-29

www.national.com 8

Start-Up Characteristics

LM4050-5.0 RS= 30k

LM4050

LM4050-2.5 RS= 30k

DS101045-5

DS101045-7

LM4050-10.0 RS= 30k

Functional Block Diagram

DS101045-8

DS101045-9

DS101045-14

www.national.com9

Applications Information

The LM4050 is a precision micro-power curvature-corrected

LM4050

bandgap shunt voltage reference. For space critical applica­tions, the LM4050 is available in the sub-miniature SSOT-23
surface-mount package. The LM4050 has been designed for
stable operation without the need of an external capacitor
connected between the “+” pin and the “−” pin. If, however, a
bypass capacitor is used, the LM4050 remains stable. Re­ducing design effort is the availability of several fixed reverse
breakdown voltages: 2.500V, 4.096V, 5.000V, 8.192V, and

10.000V. The minimum operating current increases from
60 µA for the LM4050-2.5 to 100 µAfor the LM4050-10.0. All
versions have a maximum operating current of 15 mA.

LM4050s in the SSOT-23 packages have a parasitic Schot­tky diode between pin 2 (−) and pin 3 (Die attach interface
contact). Therefore, pin 3 of the SSOT-23 package must be
left floating or connected to pin 2.

The 4.096V version allows single +5V 12-bit ADCs or DACs
to operate with an LSB equal to 1 mV. For 12-bit ADCs or
DACs that operate on supplies of 10V or greater,the 8.192V
version gives 2 mV per LSB.

In a conventional shunt regulator application (
external series resistor (R
ply voltage and the LM4050. R
flows through the load (I
current and supply voltage may vary, R
enough to supply at least the maximum guaranteed I

) is connected between the sup-

S

determines the current that

S

) and the LM4050 (IQ). Since load

L

should be small

S

Figure 1

),an

RMIN

(spec. table) to the LM4050 even when the supply voltage is
at its minimum and the load current is at its maximum value.
When the supply voltage is at its maximum and I
minimum, R

should be large enough so that the current

S

is at its

L

flowing through the LM4050 is less than 15 mA.
R

is determined by the supply voltage, (VS), the load and

S

operating current, (I
breakdown voltage, V

and IQ), and the LM4050’s reverse

L

.

R

Typical Applications

DS101045-15

FIGURE 1. Shunt Regulator

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Typical Applications (Continued)

LM4050

**Ceramic monolithic
*Tantalum

DS101045-16

FIGURE 2. LM4050-4.1’s Nominal 4.096 breakdown voltage gives ADC12451 1 mV/LSB

www.national.com11

Typical Applications (Continued)

LM4050

FIGURE 3. Bounded amplifier reduces saturation-induced delays and can prevent succeeding stage damage.

Nominal clamping voltage is

DS101045-17

±

11.5V (LM4050’s reverse breakdown voltage +2 diode VF).

FIGURE 4. Protecting Op Amp input. The bounding voltage is±4V with the LM4050-2.5

(LM4050’s reverse breakdown voltage + 3 diode V

www.national.com 12

DS101045-18

).

F

Typical Applications (Continued)

FIGURE 5. Precision±4.096V Reference

LM4050

DS101045-19

DS101045-21

FIGURE 6. Precision 1 µA to 1 mA Current Sources

DS101045-22

www.national.com13

Physical Dimensions inches (millimeters) unless otherwise noted

Plastic Surface Mount Package (M3)

NS Package Number MF03A

(JEDEC Registration TO-236AB)

LM4050 Precision Micropower Shunt Voltage Reference

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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
labeling, can be reasonably expected to result in a
significant injury to the user.

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Corporation

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