LM4041
PRECISION MICROPOWER SHUNT VOLTAGE REFERENCES
Description
The LM4041 is a bandgap circuit designed to achieve a
precision micro-power voltage reference of 1.225 V. The
device is available in the small outline SOT23 and
SC70-5
surface mount packages which are ideal for applications
where space saving is important.
Both packages are available to 0.5% C grade and 1%
D grade for precision applications.
Excellent performance is
maintained over the 60µA to 12mA operating current range
with a typical temperature coefficient of only 20ppm/°C. The
device has been designed to be highly tolerant of capacitive
loads so maintaining excellent stability.
This device offers a pin for pin compatible alternative to the
LM4041 voltage reference in both adjustable and 1.225V
output variants.
Pin Assignments
LM4041_F (SOT23)
CATHODE
1
3
ANODE
2
N/C
Pin 3 must left floating or connected to pin 2.
LM4041_ADJF….(SOT23)
REF
1
3 ANODE
CATHODE
2
LM4041_H5
(SC70-5)
5
N/C
Features
•
•
•
•
•
•
•
•
•
•
Small packages:
SOT23, SC70-5
No output capacitor required
Output voltage tolerance
LM4041C:
±0.5% at 25°C
LM4041D:
±1% at 25°C
Low output noise:
20µVrms
(10Hz to 10kHz)
Wide operating current range: 60µA to 12mA
Extended temperature range: -40°C to +125°C
Low temperature coefficient
:
100ppm/°C (max)
All parts AEC-Q100 Grade1 qualified
ANODE
N/C
CATHODE
1
2
3
4
N/C
Pin 2 must be left floating or connected to pin 1
LM4041_ADJH5
N/C
ANODE
CATHODE
1
2
3
(SC70-5)
5
REF
4
N/C
Applications
•
•
•
•
•
•
Battery powered equipment
Precision power supplies
Portable instrumentation
Portable communications devices
Notebook and palmtop computers
Data acquisition systems
LM4041
Document number:
DS32020 Rev. 8 - 2
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LM4041
PRECISION MICROPOWER SHUNT VOLTAGE REFERENCES
Absolute Maximum Ratings
Description
Continuous Reverse Current (I
R
)
Continuous Forward Current (I
F
)
Maximum Output Voltage (LM4041_ADJ)
Junction Temperature
Storage Temperature
ESD Ratings
Human Body Model
Machine Model
Rating
20
10
15
-40 to 155
-55 to 150
4000
200
Unit
mA
mA
V
°C
°C
V
V
These are stress ratings only. Operation outside the absolute maximum ratings may cause device failure. Operation at the absolute
maximum rating, for extended periods may reduce device reliability.
Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be taken
when handling and transporting these devices.
Package Thermal Data
Package
SOT23
SC70-5
θ
JA
380°C/W
420°C/W
P
DIS
T
A
= 25°C, T
J
= 150°C
330mW
300mW
Recommended Operating Conditions
Parameter
Reverse Current
Output Voltage Range
Operating Ambient Temperature Range
Min
0.06
1.24
-40
Max
12
10
125
Units
mA
V
°C
LM4041
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LM4041
PRECISION MICROPOWER SHUNT VOLTAGE REFERENCES
Electrical Characteristics
LM4041-1.2
Electrical characteristics over recommended operating conditions, T
A
= 25°C, unless otherwise stated, I
RMIN
<I
R
<12mA, V
REF
<V
OUT
<10V.
LM4041C and LM4041D have initial tolerances of 0.5% and 1% respectively.
Symbol
Parameter
Reverse Breakdown Voltage
Conditions
T
A
25°C
25°C
-40 to 85°C
-40 to 125°C
25°C
-40 to 85°C
-40 to 125°C
-40 to 125°C
Typ
1.225
LM4041C
Limits
±6
±14
±18.4
60
65
68
±100
1.5
2.0
2.0
6.0
8.0
8.0
1.5
LM4041D
Limits
±12
±24
±31
65
70
73
±150
2.0
2.5
2.5
8.0
10.0
10.0
2.0
Units
V
mV
V
REF
Reverse Breakdown Voltage
Tolerance
Minimum Operating Current
I
R
= 100 µA
I
RMIN
45
±20
±15
±15
0.7
µA
Average Reverse Breakdown
ΔV
R
/ΔΤ
Voltage Temperature Coefficient
I
R
= 10 mA
I
R
= 1 mA,
I
R
= 100 µA
I
RMIN
< I
R
< 1mA
ppm/°C
25°C
-40 to 85°C
-40 to 125°C
Reverse Breakdown Change With
ΔV
R
/ΔΙ
R
Current
25°C
1mA < I
R
< 12 mA
-40 to 85°C
-40 to 125°C
Z
R
Dynamic Output Impedance
I
R
= 1mA, f = 120Hz, I
AC
= 0.1I
R
e
n
Noise Voltage
I
R
= 100µA 10Hz < f < 10kHz
Long Term Stability (Non
t = 1000Hrs I
R
= 100µA
ΔV
R
cumulative)
mV
2.5
0.5
20
120
Ω
µV
RMS
ppm
LM4041-Adj
Electrical characteristics over recommended operating conditions, T
A
= 25°C, I
RMIN
<I
R
<12 mA, V
REF
<V
OUT
<10V unless otherwise stated. The
grade D designates initial reference voltage tolerance of ±1% and is measured at an output/cathode voltage of 5V.
Symbol
Parameter
Reverse Breakdown Voltage
Conditions
T
A
25°C
25°C
-40 to 85°C
-40 to 125°C
25°C
-40 to 85°C
-40 to 125°C
-40 to 125°C
25°C
-40 to 85°C
-40 to 125°C
25°C
-40 to 85°C
-40 to 125°C
25°C
-40 to 85°C
-40 to 125°C
25°C
-40 to 85°C
-40 to 125°C
V
KA
= V
REF
Typ
1.233
LM4041D
Limits
±12
±24
±30
65
70
73
±150
-2.5
-3.0
-4.0
150
200
200
2.0
2.5
2.5
6.0
8.0
10.0
Units
V
mV
V
REF
Reverse Breakdown Voltage
Tolerance
Minimum Operating Current
I
R
= 100 µA, V
KA
= 5V
I
RMIN
45
±20
±15
±15
-1.55
µA
Average Reverse Breakdown
ΔV
R
/ΔΤ
Voltage Temperature
Coefficient
ΔV
R
/ΔV
K
I
R
= 10 mA
I
R
= 1 mA,
I
R
= 100 µA
ppm/°C
Reference voltage change with
I
R
= 1mA
cathode voltage change
Reference input current
I
RMIN
< I
R
< 1mA
V
OUT
> 1.6V
1mA < I
R
< 12 mA
V
OUT
> 1.6V
mV/V
I
REF
60
nA
0.7
ΔV
R
/ΔΙ
R
Reverse Breakdown Change
With Current
mV
2
0.5
2
20
120
Z
R
e
n
ΔV
R
Dynamic Output Impedance
Noise Voltage
Long Term Stability
(Non cumulative)
I
R
= 1mA,
f = 120Hz
V
KA
= 10V
I
AC
= 0.1I
R
I
R
= 100µA 10Hz < f < 10kHz
t = 1000Hrs
I
R
= 100µA
Ω
µV
RMS
ppm
LM4041
Document number:
DS32020 Rev. 8 - 2
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September 2011
© Diodes Incorporated
LM4041
PRECISION MICROPOWER SHUNT VOLTAGE REFERENCES
Typical Characteristics
LM4041 1.225
100
150uA, no cap
Reference Impedance (Ω)
10
150uA, 1uF
1mA, no cap
1
1mA, 1µF tant
0.1
0.01
0.1
1
10
Frequency (kHz)
100
1000
Output Impedance vs. Frequency
LM4041
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LM4041
PRECISION MICROPOWER SHUNT VOLTAGE REFERENCES
Application Information
In a conventional shunt regulator application (Figure
1),
an
external series resistor (R
S
) is connected between the
supply voltage, V
S
, and the LM4041.
V
S
I
R
+ I
L
R
S
I
L
V
O
V
S
I
R
+
I
L
I
L
V
R
I
R
R
S
I
R
V
R
Figure 2
Figure 1
R
S
determines the current that flows through the load (I
L
)
and the LM4041 (I
R
). Since load current and supply
voltage may vary, R
S
should be small enough to supply at
least the minimum acceptable I
R
to the LM4040 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
L
is at its minimum, R
S
should be
large enough so that the current flowing through the
LM4040 is less than 12 mA.
R
S
is determined by the supply voltage, (V
S
), the load and
operating current, (I
L
and I
Q
), and the LM4040’s reverse
breakdown voltage, V
R
.
The LM4041-ADJ’s output voltage can be adjusted to any
value in the range of 1.24V through 10V. The output
voltage is set by the ratio of two external feedback
resistors as shown in Figure 2 and the internal reference
voltage (V
R
).
The output voltage is found using the equation:
⎛
R
⎞
V
O
=
V
R
× ⎜
1
+
2
⎟
⎜
R
1
⎟
⎝
⎠
Printed circuit board layout considerations
LM4041 with fixed output voltage in the SOT23 package
has the die attached to pin 1, which results in an electrical
contact between pin 2 and pin 1. Therefore, pin 1 of the
SOT23 package must be left floating or connected to
pin 2.
LM4041 with fixed output voltage in the SC70-5 package
have the die attached to pin 2, which results in an
electrical contact between pin 2 and pin 1. Therefore, pin
2 must be left floating or connected to pin1.
R
S
=
V
S
−
V
R
I
L
+
I
R
The LM4041 comes in two varients:
•
LM4041 with fixed 1.225V output
•
LM4041_ADJ with variable output voltage.
LM4041
Document number:
DS32020 Rev. 8 - 2
5 of 7
www.diodes.com
September 2011
© Diodes Incorporated