General Description
The MAX6138 is a precision, two-terminal shunt mode,
bandgap voltage reference available in fixed reverse
breakdown voltages of 1.2205V, 2.048V, 2.5V, 3.0V,
3.3V, 4.096V, and 5.0V. Ideal for space-critical applica-
tions, the MAX6138 is offered in the subminiature 3-pin
SC70 surface-mount package (1.8mm X 1.8mm), 50%
smaller than comparable devices in SOT23 surface-
mount packages.
Laser-trimmed resistors ensure precise initial accuracy.
With a 25ppm/C temperature coefficient, the device is
offered in three grades of initial accuracy ranging from
0.1% to 0.5%. The MAX6138 has a 60A to 15mA shunt-
current capability with low-dynamic impedance, ensuring
stable reverse breakdown voltage accuracy over a wide
range of operating temperatures and currents.
The MAX6138 does not require an external stabilizing
capacitor while ensuring stability with capacitive loads.
The MAX6138 is a higher precision device in a smaller
package than the LM4040/LM4050.
Applications
Portable, Battery-Powered Equipment
Notebook Computers
Cell Phones
Industrial Process Control
Features
o Ultra-Small 3-Pin SC70 Package
o 0.1% (max) Initial Accuracy
o 25ppm/C (max) Temperature Coefficient
Guaranteed Over -40C to +85C Temperature
Range
o Wide Operating Current Range: 60A to 15mA
o Low 28V
RMS
Output Noise (10Hz to 10kHz)
o 1.2205V, 2.048V, 2.5V, 3.0V, 3.3V, 4.096V, and 5.0V
Fixed Reverse Breakdown Voltages
o No Output Capacitors Required
o Stable with Capacitive Loads
MAX6138
0.1%, 25ppm, SC70 Shunt Voltage Reference
with Multiple Reverse Breakdown Voltages
________________________________________________________________ Maxim Integrated Products
1
MAX6138
I
LOAD
I
SHUNT
R
S
V
S
V
R
I
SHUNT
+ I
LOAD
-
1
3
N.C.*
+
MAX6138
SC70
TOP VIEW
2
*PIN 3 MUST BE LEFT FLOATING
OR CONNECTED TO PIN 2.
PART
TEMP
RANGE
PIN-
PACKAGE
OUTPUT
VOLTAGE
(V)
MAX6138_EXR12-T -40C to +85C
3 SC70-3
1.2205
MAX6138_EXR21-T -40C to +85C
3 SC70-3
2.0480
MAX6138_EXR25-T -40C to +85C
3 SC70-3
2.5000
MAX6138_EXR30-T -40C to +85C
3 SC70-3
3.0000
MAX6138_EXR33-T -40C to +85C
3 SC70-3
3.3000
MAX6138_EXR41-T -40C to +85C
3 SC70-3
4.0960
MAX6138_EXR50-T -40C to +85C
3 SC70-3
5.0000
Pin Configuration
Selector Guide
Typical Operating Circuit
19-2090; Rev 2; 4/04
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.
Ordering Information appears at end of data sheet.
MAX6138
0.1%, 25ppm, SC70 Shunt Voltage Reference
with Multiple Reverse Breakdown Voltages
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS--MAX6138_12 (1.2205V)
(I
R
= 100A, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
Reverse Current (cathode to anode) ..................................20mA
Forward Current (anode to cathode) ..................................10mA
Continuous Power Dissipation (T
A
A
= +70C)
3-Pin SC70 (derate 2.17mW/C above +70C) ...........174mW
Operating Temperature Range .........................-40C to +125C
Storage Temperature Range .............................-65C to +150C
Junction Temperature ......................................................+150C
Lead Temperature (soldering, 10s) .................................+300C
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX6138A (0.1%)
1.2193
1.2205
1.2217
MAX6138B (0.2%)
1.2181
1.2205
1.2229
Reverse Breakdown Voltage
(Note 2)
V
R
T
A
= +25C
MAX6138C (0.5%)
1.2144
1.2205
1.2266
V
Minimum Operating Current
I
RMIN
45
60
A
Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
TC
4
25
ppm/C
I
RMIN
I
R
1mA
0.3
1.0
Reverse Breakdown Voltage
Change with Operating
Current Change
V
R
/
I
R
1mA
I
R
12mA
2.5
8.0
mV
Reverse Dynamic
Impedance (Note 3)
Z
R
I
R
= 1mA, f = 120Hz, I
AC
= 0.1I
R
0.3
0.8
Wideband Noise
e
N
I
R
= 10A, 10Hz
f 10kHz
20
V
RMS
Reverse Breakdown Voltage
V
R
t = 1000h
120
ppm
MAX6138
0.1%, 25ppm, SC70 Shunt Voltage Reference
with Multiple Reverse Breakdown Voltages
_______________________________________________________________________________________
3
ELECTRICAL CHARACTERISTICS--MAX6138_21 (2.048V)
(I
R
= 100A, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
ELECTRICAL CHARACTERISTICS--MAX6138_25 (2.5V)
(I
R
= 100A, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX6138A (0.1%)
2.0460
2.0480
2.0500
MAX6138B (0.2%)
2.0439
2.0480
2.0521
Reverse Breakdown
Voltage (Note 2)
V
R
T
A
= +25C
MAX6138C (0.5%)
2.0378
2.0480
2.0582
V
M i ni m um Op er ati ng C ur r ent
I
RMIN
45
65
A
Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
TC
4
25
ppm/C
I
RMIN
I
R
1mA
0.3
1.0
Reverse Breakdown
Voltage Change with
Operating Current Change
V
R
/
I
R
1mA
I
R
15mA
2.5
8.0
mV
Reverse Dynamic
Impedance (Note 3)
Z
R
I
R
= 1mA, f = 120Hz, I
AC
= 0.1I
R
0.3
0.8
Wideband Noise
e
N
10Hz
f 10kHz
28
V
RMS
Rever se Br eakd ow n
V ol tag e Long - Ter m S tab i l i ty
V
R
t = 1000h
120
ppm
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX6138A (0.1%)
2.4975
2.5000
2.5025
MAX6138B (0.2%)
2.4950
2.5000
2.5050
Reverse Breakdown Voltage
(Note 2)
V
R
T
A
= +25C
MAX6138C (0.2%)
2.4875
2.5000
2.5125
V
Minimum Operating Current
I
RMIN
45
65
A
Reverse Voltage Temperature
Coefficient (Notes 2, 3)
TC
4
25
ppm/C
Reverse Breakdown Voltage
Change with Operating Current
Change
V
R
/
I
R
I
RMIN
I
R
1mA
0.3
1.0
mV
Rever se Br eakd ow n V ol tag e
C hang e w i th Op er ati ng C ur r ent
C hang e
V
R
/
I
R
1mA
I
R
15mA
2.5
8.0
mV
Reverse Dynamic Impedance
(Note 3)
Z
R
I
R
= 1mA, f = 120Hz, I
AC
= 0.1I
R
0.3
0.8
Wideband Noise
e
N
10Hz
f 10kHz
35
V
RMS
Reverse Breakdown Voltage
Long-Term Stability
V
R
t = 1000h
120
ppm
MAX6138
0.1%, 25ppm, SC70 Shunt Voltage Reference
with Multiple Reverse Breakdown Voltages
4
_______________________________________________________________________________________
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX6138A (0.1%)
2.9970
3.0000
3.0030
MAX6138B (0.2%)
2.9940
3.0000
3.0060
Reverse Breakdown
Voltage (Note 2)
V
R
T
A
= +25C
MAX6138C (0.5%)
2.9850
3.0000
3.0150
V
Minimum Operating
Current
I
RMIN
45
65
A
Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
TC
4
25
ppm/C
I
RMIN
I
R
1mA
0.3
1.0
Reverse Breakdown
Voltage Change with
Operating Current Change
V
R
/
I
R
1mA
I
R
15mA
2.5
8.0
mV
Reverse Dynamic
Impedance (Note 3)
Z
R
I
R
= 1mA, f =120Hz, I
AC
= 0.1I
R
0.3
0.8
Wideband Noise
e
N
10Hz
f 10kHz
45
V
RMS
Reverse Breakdown
Voltage Long-Term
Stability
V
R
t = 1000h
120
ppm
ELECTRICAL CHARACTERISTICS--MAX6138_30 (3.0V)
(I
R
= 100A, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX6138A (0.1%)
3.2967
3.3000
3.3033
MAX6138B (0.2%)
3.2934
3.3000
3.3066
Reverse Breakdown
Voltage (Note 2)
V
R
T
A
= +25C
MAX6138C (0.5%)
3.2835
3.3000
3.3165
V
M i ni m um Op er ati ng C ur r ent
I
RMIN
45
67
A
Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
TC
4
25
ppm/C
I
RMIN
I
R
1mA
0.3
1.0
Reverse Breakdown
Voltage Change with
Operating Current Change
V
R
/
I
R
1mA
I
R
15mA
8.0
mV
Reverse Dynamic
Impedance (Note 3)
Z
R
I
R
= 1mA, f =120Hz, I
AC
= 0.1I
R
0.3
0.8
Wideband Noise
e
N
10Hz
f 10kHz
50
V
RMS
Reverse Breakdown
Voltage Long-Term
Stability
V
R
t = 1000h
120
ppm
ELECTRICAL CHARACTERISTICS--MAX6138_33 (3.3V)
(I
R
= 100A, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
MAX6138
0.1%, 25ppm, SC70 Shunt Voltage Reference
with Multiple Reverse Breakdown Voltages
_______________________________________________________________________________________
5
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX6138A (0.1%)
4.0919
4.0960
4.1001
MAX6138B (0.2%)
4.0878
4.0960
4.1042
Reverse Breakdown
Voltage (Note 2)
VR
T
A
= +25C
MAX6138C (0.5%)
4.0755
4.0960
4.1165
V
Minimum Operating
Current
IRMIN
50
73
A
Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
TC
4
25
ppm/C
I
RMIN
I
R
1mA
0.5
1.2
Reverse Breakdown
Voltage Change with
Operating Current Change
VR/IR
1mA
I
R
15mA
3.0
10.0
mV
Reverse Dynamic
Impedance (Note 3)
ZR
I
R
= 1mA, f = 120Hz, I
AC
= 0.1I
R
0.5
1.0
Wideband Noise
eN
10Hz
f 10kHz
64
V
RMS
Reverse Breakdown
Voltage Long-Term
Stability
VR
t = 1000h
120
ppm
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX6138A (0.1%)
4.9950
5.0000
5.0050
MAX6138B (0.2%)
4.9900
5.0000
5.0100
Reverse Breakdown
Voltage (Note 2)
V
R
T
A
= +25C
MAX6138C (0.5%)
4.9750
5.0000
5.0250
V
M i ni m um Op er ati ng C ur r ent
I
RMIN
54
80
A
Reverse Voltage
Temperature Coefficient
(Notes 2, 3)
TC
4
25
ppm/C
I
RMIN
I
R
1mA
0.5
1.4
Reverse Breakdown
Voltage Change with
Operating Current Change
V
R
/
I
R
1mA
I
R
15mA
3.5
12.0
mV
Reverse Dynamic
Impedance (Note 3)
Z
R
I
R
= 1mA, f = 120Hz, I
AC
= 0.1I
R
0.5
1.1
Wideband Noise
e
N
10Hz
f 10kHz
80
V
RMS
Rever se Br eakd ow n
V ol tag e Long - Ter m S tab i l i ty
V
R
t = 1000h
120
ppm
ELECTRICAL CHARACTERISTICS--MAX6138_41 (4.096V)
(I
R
= 100A, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
ELECTRICAL CHARACTERISTICS--MAX6138_50 (5.0V)
(I
R
= 100A, T
A
= -40C to +85C, unless otherwise noted. Typical values are at T
A
= +25C.) (Note 1)
Note 1: All devices are 100% production tested at +25C and are guaranteed by correlation for T
A
= T
MAX
to T
MIN
, as specified.
Note 2: TC is measured by the "box" method, i.e. (V
MAX
- V
MIN
) / (T
MAX
- T
MIN
)
Note 3: Guaranteed by design.
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