NSC LM4050CIM3 Precision micropower shunt voltage reference Datasheet

LM4050
Precision Micropower Shunt Voltage Reference
General Description
Ideal for space critical applications, the LM4050 precision
voltage reference is available in the sub-miniature (3 mm x
1.3 mm) SOT-23 surface-mount package. The LM4050’s design eliminates the need 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 breakdown voltages:
2.048V, 2.500V, 4.096V, 5.000V, 8.192V, and 10.000V. The
minimum operating current increases from 60 µA for the
LM4050-2.0 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 ± 0.1% (A grade) at 25˚C.
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 are available
in both an industrial temperature range (−40˚C and +85˚C)
and an extended temperature range (−40˚C and +125˚C).
Features
n Small packages: SOT-23
n No output capacitor required
n Tolerates capacitive loads
n Fixed reverse breakdown voltages of 2.048V, 2.500V,
4.096V, 5.000V, 8.192V, and 10.000V
Key Specifications (LM4050-2.5)
j Output voltage tolerance
(A grade, 25˚C)
± 0.1% (max)
j Low output noise
(10 Hz to 10 kHz)
41 µVrms(typ)
j Wide operating current range
60 µA to 15 mA
j Industrial temperature range
−40˚C to +85˚C
j Extended temperature range
−40˚C to +125˚C
j Low temperature coefficient
50 ppm/˚C (max)
Applications
n
n
n
n
n
n
n
n
Portable, Battery-Powered Equipment
Data Acquisition Systems
Instrumentation
Process Control
Energy Management
Product Testing
Automotive
Precision Audio Components
Connection Diagram
SOT-23
10104501
*This pin must be left floating or connected to pin 2.
Top View
See NS Package Number MF03A
© 2004 National Semiconductor Corporation
DS101045
www.national.com
LM4050 Precision Micropower Shunt Voltage Reference
July 2004
LM4050
Ordering Information
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
LM4050 Supplied as 3000 Units,
Tape and Reel
LM4050AIM3-2.0
LM4050AIM3X-2.0
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
LM4050BIM3-2.0
LM4050BIM3X-2.0
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
LM4050CIM3-2.0
LM4050CIM3X-2.0
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
Extended Temperature Range (−40˚C to +125˚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)
www.national.com
LM4050 Supplied as 1000 Units,
Tape and Reel
LM4050 Supplied as 3000 Units,
Tape and Reel
LM4050AEM3-2.0
LM4050AEM3X-2.0
LM4050AEM3-2.5
LM4050AEM3X-2.5
LM4050AEM3-4.1
LM4050AEM3X-4.1
LM4050AEM3-5.0
LM4050AEM3X-5.0
LM4050AEM3-8.2
LM4050AEM3X-8.2
LM4050AEM3-10
LM4050AEM3X-10
LM4050BEM3-2.0
LM4050BEM3X-2.0
LM4050BEM3-2.5
LM4050BEM3X-2.5
LM4050BEM3-4.1
LM4050BEM3X-4.1
LM4050BEM3-5.0
LM4050BEM3X-5.0
LM4050BEM3-8.2
LM4050BEM3X-8.2
LM4050BEM3-10
LM4050BEM3X-10
LM4050CEM3-2.0
LM4050CEM3X-2.0
LM4050CEM3-2.5
LM4050CEM3X-2.5
LM4050CEM3-4.1
LM4050CEM3X-4.1
LM4050CEM3-5.0
LM4050CEM3X-5.0
LM4050CEM3-8.2
LM4050CEM3X-8.2
LM4050CEM3-10
LM4050CEM3X-10
2
Only three fields of marking are possible on the SOT-23’s small surface. This table gives the meaning of the three fields.
Part Marking
RCA
RDA
REA
Field Definition
First Field:
R = Reference
Second Field:
RFA
N = 2.048V Voltage Option
RGA
C = 2.500V Voltage Option
RNA
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:
RNB
RCC
A–C = Initial Reverse Breakdown Voltage or Reference Voltage Tolerance
RDC
A = ± 0.1%, B = ± 0.2%, C = +0.5%,
REC
RFC
RGC
RNC
3
www.national.com
LM4050
SOT-23 Package Marking Information
LM4050
Absolute Maximum Ratings (Note 1)
Operating Ratings (Note 2)
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 (TA = 25˚C) (Note 2)
Industrial Temperature
Range
−40˚C ≤ TA ≤ +85˚C
Extended temperature
Range
−40˚C ≤ TA ≤ +125˚C
Reverse Current
M3 Package
Storage Temperature
(Tmin ≤ TA ≤ Tmax)
Temperature Range
280 mW
LM4050-2.0
60 µA to 15 mA
−65˚C to +150˚C
LM4050-2.5
60 µA to 15 mA
LM4050-4.1
68 µA to 15 mA
LM4050-5.0
74 µA to 15 mA
Lead Temperature
M3 Package
Vapor phase (60 seconds)
+215˚C
LM4050-8.2
91 µA to 15 mA
Infrared (15 seconds)
+220˚C
LM4050-10.0
100 µA to 15 mA
ESD Susceptibility
Human Body Model (Note 3)
2 kV
Machine Model (Note 3)
200V
See AN-450 “Surface Mounting Methods and Their Effect
on Product Reliability” for other methods of soldering
surface mount devices.
LM4050-2.0
Electrical Characteristics
Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial
Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2%, and 0.5% respectively.
Symbol
VR
IRMIN
∆VR/∆T
∆VR/∆IR
Parameter
Conditions
Typical
(Note 4)
LM4050AIM3
LM4050AEM3
Limits
(Note 5)
LM4050BIM3
LM4050BEM3
Limits
(Note 5)
LM4050CIM3
LM4050CEM3
Limits
(Note 5)
Units
(Limit)
Reverse Breakdown Voltage
IR = 100 µA
Reverse Breakdown Voltage
Tolerance (Note 6)
IR = 100 µA
2.048
± 2.048
± 4.096
± 10.24
mV (max)
Industrial Temp. Range
± 9.0112
± 11.4688
± 14.7456
mV (max)
Extended Temp. Range
± 12.288
± 14.7456
± 17.2032
mV (max)
60
60
60
µA (max)
65
65
65
µA (max)
Minimum Operating Current
Average Reverse Breakdown
Voltage Temperature
Coefficient (Note 6)
Reverse Breakdown Voltage
Change with Operating Current
Change (Note 7)
V
41
IR = 10 mA
± 20
IR = 1 mA
± 15
IR = 100 µA
± 15
IRMIN ≤ IR ≤ 1 mA
0.3
1 mA ≤ IR ≤ 15 mA
µA
ppm/˚C
ppm/˚C
± 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)
mV
2.3
mV
ZR
Reverse Dynamic Impedance
IR = 1 mA, f = 120 Hz, IAC
= 0.1 IR
0.3
Ω
eN
Wideband Noise
IR = 100 µA
34
µVrms
ppm
10 Hz ≤ f ≤ 10 kHz
∆VR
Reverse Breakdown Voltage
Long Term Stability
t = 1000 hrs
T = 25˚C ± 0.1˚C
IR = 100 µA
120
VHYST
Thermal Hysteresis
(Note 8)
∆T = −40˚C to 125˚C
0.7
www.national.com
4
mV
LM4050
LM4050-2.5
Electrical Characteristics
Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial
Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2%, and 0.5% respectively.
Symbol
VR
IRMIN
∆VR/∆T
∆VR/∆IR
Parameter
Typical
(Note 4)
Conditions
LM4050AIM3 LM4050BIM3 LM4050CIM3
LM4050AEM3 LM4050BEM3 LM4050CEM3
Limits
Limits
Limits
(Note 5)
(Note 5)
(Note 5)
2.500
Units
(Limit)
Reverse Breakdown Voltage
IR = 100 µA
Reverse Breakdown Voltage
Tolerance (Note 6)
IR = 100 µA
± 2.5
± 5.0
± 13
mV (max)
Industrial Temp. Range
± 11
± 14
± 21
mV (max)
Extended Temp. Range
± 15
± 18
± 25
mV (max)
60
60
60
µA (max)
65
65
65
µA (max)
Minimum Operating Current
Average Reverse Breakdown
Voltage Temperature Coefficient
(Note 6)
Reverse Breakdown Voltage
Change with Operating Current
Change (Note 7)
V
41
IR = 10 mA
± 20
IR = 1 mA
± 15
IR = 100 µA
± 15
IRMIN ≤ IR ≤ 1 mA
0.3
1 mA ≤ IR ≤ 15 mA
µA
ppm/˚C
ppm/˚C
± 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)
mV
2.3
mV
ZR
Reverse Dynamic Impedance
IR = 1 mA, f = 120 Hz, IAC
= 0.1 IR
0.3
Ω
eN
Wideband Noise
IR = 100 µA
41
µVrms
10 Hz ≤ f ≤ 10 kHz
∆VR
Reverse Breakdown Voltage
Long Term Stability
t = 1000 hrs
T = 25˚C ± 0.1˚C
IR = 100 µA
120
ppm
VHYST
Thermal Hysteresis
(Note 8)
∆T = −40˚C to 125˚C
0.7
mV
LM4050-4.1
Electrical Characteristics
Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial
Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2%, and 0.5% respectively.
Symbol
VR
IRMIN
∆VR/∆T
∆VR/∆IR
Parameter
Typical
(Note 4)
Conditions
LM4050AIM3 LM4050BIM3 LM4050CIM3
LM4050AEM3 LM4050BEM3 LM4050CEM3
Limits
Limits
Limits
(Note 5)
(Note 5)
(Note 5)
4.096
Units
(Limit)
Reverse Breakdown Voltage
IR = 100 µA
Reverse Breakdown Voltage
Tolerance (Note 6)
IR = 100 µA
± 4.1
± 8.2
± 21
mV (max)
Industrial Temp. Range
± 18
± 22
± 34
mV (max)
Extended Temp. Range
± 25
± 29
± 41
mV (max)
68
68
68
µA (max)
Industrial Temp. Range
73
73
73
µA (max)
Extended Temp. Range
78
78
78
µA (max)
Minimum Operating Current
Average Reverse Breakdown
Voltage Temperature Coefficient
(Note 6)
Reverse Breakdown Voltage
Change with Operating Current
Change (Note 7)
V
52
IR = 10 mA
± 30
IR = 1 mA
± 20
IR = 100 µA
± 20
IRMIN ≤ IR ≤ 1 mA
0.2
1 mA ≤ IR ≤ 15 mA
µA
ppm/˚C
ppm/˚C
± 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)
mV
2.0
5
mV
www.national.com
LM4050
LM4050-4.1
Electrical Characteristics
(Continued)
Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial
Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2%, and 0.5% respectively.
Symbol
ZR
Parameter
Reverse Dynamic Impedance
Typical
(Note 4)
Conditions
IR = 1 mA, f = 120 Hz,
LM4050AIM3 LM4050BIM3 LM4050CIM3
LM4050AEM3 LM4050BEM3 LM4050CEM3
Limits
Limits
Limits
(Note 5)
(Note 5)
(Note 5)
Units
(Limit)
0.5
Ω
93
µVrms
120
ppm
1.148
mV
IAC = 0.1 IR
eN
Wideband Noise
IR = 100 µA
10 Hz ≤ f ≤ 10 kHz
∆VR
Reverse Breakdown Voltage
Long Term Stability
t = 1000 hrs
T = 25˚C ± 0.1˚C
IR = 100 µA
VHYST
Thermal Hysteresis
(Note 8)
∆T = −40˚C to 125˚C
LM4050-5.0
Electrical Characteristics
Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial
Reverse Breakdown Voltage tolerances of ± 0.1%, ± 0.2% and 0.5% respectively.
Symbol
VR
IRMIN
∆VR/∆T
∆VR/∆IR
Parameter
Typical
(Note 4)
Conditions
5.000
IR = 100 µA
Reverse Breakdown Voltage
Tolerance (Note 6)
IR = 100 µA
± 5.0
± 10
± 25
mV (max)
Industrial Temp. Range
± 22
± 27
± 42
mV (max)
Extended Temp. Range
± 30
± 35
± 50
mV (max)
74
74
74
µA (max)
Industrial Temp. Range
80
80
80
µA (max)
Extended Temp. Range
90
90
90
µA (max)
Minimum Operating Current
Average Reverse Breakdown
Voltage Temperature Coefficient
(Note 6)
Reverse Breakdown Voltage
Change with Operating Current
Change (Note 7)
Reverse Dynamic Impedance
Wideband Noise
V
56
IR = 10 mA
± 30
IR = 1 mA
± 20
IR = 100 µA
± 20
IRMIN ≤ IR ≤ 1 mA
0.2
µA
ppm/˚C
ppm/˚C
± 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)
mV
2.0
IR = 1 mA, f = 120 Hz,
0.5
mV
Ω
Ω (max)
IAC = 0.1 IR
eN
Units
(Limit)
Reverse Breakdown Voltage
1 mA ≤ IR ≤ 15 mA
ZR
LM4050AIM3 LM4050BIM3 LM4050CIM3
LM4050AEM3 LM4050BEM3 LM4050CEM3
Limits
Limits
Limits
(Note 5)
(Note 5)
(Note 5)
IR = 100 µA
93
µVrms
120
ppm
1.4
mV
10 Hz ≤ f ≤ 10 kHz
∆VR
Reverse Breakdown Voltage
Long Term Stability
t = 1000 hrs
T = 25˚C ± 0.1˚C
IR = 100 µA
VHYST
Thermal Hysteresis
(Note 8)
www.national.com
∆T = −40˚C to 125˚C
6
LM4050
LM4050-8.2
Electrical Characteristics
Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial
Reverse Breakdown Voltage tolerances of ± 0.1% and ± 0.2% and 0.5% respectively.
Symbol
VR
IRMIN
∆VR/∆T
∆VR/∆IR
Parameter
Typical
(Note 4)
Conditions
8.192
Units
(Limit)
Reverse Breakdown Voltage
IR = 150 µA
Reverse Breakdown Voltage
Tolerance (Note 6)
IR = 150 µA
± 8.2
± 16
± 41
mV (max)
Industrial Temp. Range
± 35
± 43
± 68
mV (max)
Extended Temp. Range
± 49
± 57
± 82
mV (max)
91
91
91
µA (max)
Minimum Operating Current
Average Reverse Breakdown
Voltage Temperature Coefficient
(Note 6)
Reverse Breakdown Voltage
Change with Operating Current
Change (Note 7)
Reverse Dynamic Impedance
V
74
µA
Industrial Temp. Range
95
95
95
µA (max)
Extended Temp. Range
100
100
100
µA (max)
IR = 10 mA
± 40
IR = 1 mA
± 20
IR = 150 µA
± 20
IRMIN ≤ IR ≤ 1 mA
0.6
1 mA ≤ IR ≤ 15 mA
ZR
LM4050AIM3 LM4050BIM3 LM4050CIM3
LM4050AEM3 LM4050BEM3 LM4050CEM3
Limits
Limits
Limits
(Note 5)
(Note 5)
(Note 5)
ppm/˚C
ppm/˚C
± 50
± 50
± 50
ppm/˚C (max)
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)
mV
7.0
IR = 1 mA, f = 120 Hz,
mV
0.6
Ω
150
µVrms
120
ppm
2.3
mV
IAC = 0.1 IR
eN
Wideband Noise
IR = 150 µA
10 Hz ≤ f ≤ 10 kHz
∆VR
Reverse Breakdown Voltage
Long Term Stability
t = 1000 hrs
T = 25˚C ± 0.1˚C
IR = 150 µA
VHYST
Thermal Hysteresis
(Note 8)
∆T = −40˚C to 125˚C
7
www.national.com
LM4050
LM4050-10.0
Electrical Characteristics
Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = 25˚C. The grades A, B and C designate initial
Reverse Breakdown Voltage tolerances of ± 0.1% and ± 0.2% and 0.5% respectively.
Symbol
VR
Parameter
Typical
(Note 4)
Conditions
10.00
∆VR/∆T
∆VR/∆IR
IR = 150 µA
Reverse Breakdown Voltage
Tolerance (Note 6)
IR = 150 µA
± 10
± 20
Industrial Temp. Range
± 43
± 53
± 83
mV (max)
Extended Temp. Range
± 60
± 70
± 100
mV (max)
100
100
100
µA (max)
Industrial Temp. Range
103
103
103
µA (max)
Extended Temp. Range
110
110
110
µA (max)
Average Reverse Breakdown
Voltage Temperature Coefficient
(Note 6)
Reverse Breakdown Voltage
Change with Operating Current
Change (Note 7)
Reverse Dynamic Impedance
V
± 50
80
IR = 10 mA
± 40
IR = 1 mA
± 20
IR = 150 µA
± 20
IRMIN ≤ IR ≤ 1 mA
0.8
1 mA ≤ IR ≤ 15 mA
ZR
Units
(Limit)
Reverse Breakdown Voltage
Minimum Operating Current
IRMIN
LM4050AIM3 LM4050BIM3 LM4050CIM3
LM4050AEM3 LM4050BEM3 LM4050CEM3
Limits
Limits
Limits
(Note 5)
(Note 5)
(Note 5)
µA
ppm/˚C
ppm/˚C
± 50
± 50
± 50
ppm/˚C (max)
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)
mV
8.0
IR = 1 mA, f = 120 Hz,
mV (max)
mV
0.7
Ω
150
µVrms
120
ppm
2.8
mV
IAC = 0.1 IR
eN
Wideband Noise
IR = 150 µA
10 Hz ≤ f ≤ 10 kHz
∆VR
Reverse Breakdown Voltage
Long Term Stability
t = 1000 hrs
T = 25˚C ± 0.1˚C
IR = 150 µA
VHYST
Thermal Hysteresis
(Note 8)
∆T = −40˚C to 125˚C
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. 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: The maximum power dissipation must be derated at elevated temperatures and is dictated by TJmax (maximum junction temperature), θJA (junction to
ambient thermal resistance), and TA (ambient temperature). The maximum allowable power dissipation at any temperature is PDmax = (TJmax − TA)/θJA or the
number given in the Absolute Maximum Ratings, whichever is lower. For the LM4050, TJmax = 125˚C, and the typical thermal resistance (θJA), when board mounted,
is 326˚C/W for the SOT-23 package.
Note 3: 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
directly into each pin.
Note 4: Typicals are at TJ = 25˚C and represent most likely parametric norm.
Note 5: Limits are 100% 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 6: The boldface (over-temperature) limit for Reverse Breakdown Voltage Tolerance is defined as the room temperature Reverse Breakdown Voltage Tolerance
± [(∆V R/∆T)(max∆T)(VR)]. Where, ∆VR/∆T is the VR temperature coefficient, max∆T is the maximum difference in temperature from the reference point of 25˚C to
T MIN or TMAX, and VR is the reverse breakdown voltage. The total over-temperature tolerance for the different grades in the industrial temperature range where
max∆T = 65˚C is shown below:
A-grade: ± 0.425% = ± 0.1% ± 50 ppm/˚C x 65˚C
B-grade: ± 0.525% = ± 0.2% ± 50 ppm/˚C x 65˚C
C-grade: ± 0.825% = ± 0.5% ± 50 ppm/˚C x 65˚C
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 7: 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.
Note 8: Thermal hysteresis is defined as the difference in voltage measured at +25˚C after cycling to temperature -40˚C and the 25˚C measurement after cycling
to temperature +125˚C.
www.national.com
8
LM4050
Typical Performance Characteristics
Output Impedance vs Frequency
Output Impedance vs Frequency
10104510
10104511
Reverse Characteristics and
Minimum Operating Current
Noise Voltage vs Frequency
10104512
10104513
Thermal Hysteresis
10104529
9
www.national.com
LM4050
Start-Up Characteristics
LM4050-10.0
RS = 30k
10104505
LM4050-2.5
RS = 30k
10104509
10104507
LM4050-5.0
RS = 30k
10104508
www.national.com
10
LM4050
Functional Block Diagram
10104514
temperature +125˚C and again measured at 25˚C. The resulting VOUT delta shift between the 25˚C measurements is
thermal hysteresis. Thermal hysteresis is common in precision references and is induced by thermal-mechanical package stress. Changes in environmental storage temperature,
operating temperature and board mounting temperature are
all factors that can contribute to thermal hysteresis.
In a conventional shunt regulator application (Figure 1) , an
external series resistor (RS) is connected between the supply voltage and the LM4050. RS determines the current that
flows through the load (IL) and the LM4050 (IQ). Since load
current and supply voltage may vary, RS should be small
enough to supply at least the maximum guaranteed IRMIN
(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 IL is at its
minimum, RS should be large enough so that the current
flowing through the LM4050 is less than 15 mA.
RS is determined by the supply voltage, (VS), the load and
operating current, (IL and IQ), and the LM4050’s reverse
breakdown voltage, VR.
Applications Information
The LM4050 is a precision micro-power curvature-corrected
bandgap shunt voltage reference. For space critical applications, the LM4050 is available in the sub-miniature SOT-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: 2.048V, 2.500V, 4.096V, 5.000V,
8.192V, and 10.000V. The minimum operating current increases from 60 µA for the LM4050-2.0 to 100 µA for the
LM4050-10.0. All versions have a maximum operating current of 15 mA.
LM4050s in the SOT-23 packages have a parasitic Schottky
diode between pin 2 (−) and pin 3 (Die attach interface
contact). Therefore, pin 3 of the SOT-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.
The typical thermal hysteresis specification is defined as the
change in +25˚C voltage measured after thermal cycling.
The device is thermal cycled to temperature -40˚C and then
measured at 25˚C. Next the device is thermal cycled to
Typical Applications
10104515
FIGURE 1. Shunt Regulator
11
www.national.com
LM4050
Typical Applications
(Continued)
10104516
**Ceramic monolithic
*Tantalum
FIGURE 2. LM4050-4.1’s Nominal 4.096 breakdown voltage gives ADC12451 1 mV/LSB
www.national.com
12
LM4050
Typical Applications
(Continued)
10104517
FIGURE 3. Bounded amplifier reduces saturation-induced delays and can prevent succeeding stage damage.
Nominal clamping voltage is ± 11.5V (LM4050’s reverse breakdown voltage +2 diode VF).
10104518
FIGURE 4. Protecting Op Amp input. The bounding voltage is ± 4V with the LM4050-2.5
(LM4050’s reverse breakdown voltage + 3 diode VF).
13
www.national.com
LM4050
Typical Applications
(Continued)
10104519
FIGURE 5. Precision ± 4.096V Reference
10104521
10104522
FIGURE 6. Precision 1 µA to 1 mA Current Sources
www.national.com
14
LM4050 Precision Micropower Shunt Voltage Reference
Physical Dimensions
inches (millimeters) unless otherwise noted
Plastic Surface Mount Package (M3)
NS Package Number MF03A
(JEDEC Registration TO-236AB)
LIFE SUPPORT POLICY
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
labeling, can be reasonably expected to result in a
significant injury to the user.
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.
BANNED SUBSTANCE COMPLIANCE
National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products
Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification
(CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2.
National Semiconductor
Americas Customer
Support Center
Email: [email protected]
Tel: 1-800-272-9959
www.national.com
National Semiconductor
Europe Customer Support Center
Fax: +49 (0) 180-530 85 86
Email: [email protected]
Deutsch Tel: +49 (0) 69 9508 6208
English Tel: +44 (0) 870 24 0 2171
Français Tel: +33 (0) 1 41 91 8790
National Semiconductor
Asia Pacific Customer
Support Center
Email: [email protected]
National Semiconductor
Japan Customer Support Center
Fax: 81-3-5639-7507
Email: [email protected]
Tel: 81-3-5639-7560
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.
Similar pages