AS4040
Precision Micropower 2.5V Shunt Voltage Reference
•
Low temperature coefficient 100 ppm/°C
•
Operating current range 100µA to 15 mA
•
Low power, 250 mW @ Iin=100 mA
•
Two terminal "Zener" operation
•
Small package: SOT - 23, TO-92, and SO-8
•
Fixed reverse breakdown voltage 2.5 Volt
•
No output capacitance required
•
Similar replacement for LM4040
FEATURES
•
Constant Current Source
•
Digital Voltmeter
•
Power Supply Monitor
•
Precision Regulators
•
Battery-Powered Equipment
•
Instrumentation
•
Automotive Electronics
•
Data Acquisition Systems
•
Energy Management
APPLICATIONS
PRODUCT DESCRIPTION
The AS4040 is a two-terminal, temperature compensated, band-gap voltage reference, which provides a fixed 2.5V output for input
currents between 100
µA
to 15mA. The bandgap voltage (2.5V) is independently trimmed from the output voltage to achieve a very
low tempco. This trimming technique process gives a very stable device over the full temperature range (A grade 50 ppm/
°C).
The
AS4040 is available in the sub-miniature (3mm
×
1.3mm) SOT-23, SO-8 surface mount package, or TO-92 package. The operating
temperature is -40°C to 85°C.
The AS4040 advanced design eliminates the need for an external stabilized capacitor while insuring stability with any capacitive load,
making them easy to use.
ORDERING INFORMATION
Part Number
AS4041YN-X
AS4041YS-X
AS4041YM-X
Package Type
TO-92
SO-8
SOT-23
Temperature Coef.
Y= A=100ppm/°C
B=150ppm/°C
Output Accuracy
1=0.5%
2=1%
3=2%
Reverse Breakdown Voltage
2.5 = 2.5V
5.0 = 5.0V
X=
V=
Note: Consult factory for lower tempco and tolerance.
PIN CONNECTIONS
8-Pin Surface Mount (S)
N/C
N/C
N/C
-
1
2
3
4
8
7
6
5
+
N/C
N/C
N/C
-
3
SOT-23-3 (M)
2
1
TO-92 (N)
1
2
3
+
Bottom View
Top View
Top View
Rev. 10/11/00
AS4040
ABSOLUTE MAXIMUM RATINGS
Reverse Current................................................................20mA
Forward Current ...............................................................10mA
Storage Temperature ...................................... -65°C to +150°C
Lead Temperature (Soldering) ........................................ 300°C
Power Dissipation at 25°C
M Package ...................................................... 300mW
N Package ....................................................... 550mW
S Package........................................................ 525mW
Temperature Range ................................... -40°C
≤
T
A
≤
+85°C
ELECTRICAL CHARACTERISTICS (AS4040-2.5V)
Electrical Characteristics at I
IN
= 1000µA, and T
A
= +25°C unless otherwise noted. .
Boldface limits apply over temperature
AS4040A-2
AS4040B-2
Units
Parameters
Conditions
Min
Typ
Max
Min
Typ
Max
Reverse Breakdown
Voltage
Reverse Breakdown
Tolerance
Output Impedance
Noise Voltage
Tempco
Turn-on Setting
Operating Current Range
Temp
. Range
I
R
=500
µA
I
R
=500
µA
0.60
15
30
0.1
15
0.1
2.500
±25
±49
2
50
30
15
2.500
±25
±49
2
100
V
mV
mV
Ω
µV
p-p
ppm/°C
µSec
mA
0.1KHz≤f
≤10Hz
Note 1
0.1% of V
OUT
Note 2
0.60
15
-40
Conditions
I
R
=500
µA
I
R
=500
µA
0.60
15
30
0.1
85
-40
85
Parameters
Reverse Breakdown
Voltage
Reverse Breakdown
Tolerance
Output Impedance
Noise Voltage
Tempco
Turn-on Setting
Operating Current Range
Temp. Range
AS4040A-3
Min
Typ
Max
2.500
±50
±74
2
50
AS4040B-3
Min
Typ
Max
2.500
±50
±74
2
100
30
0.1
15
°C
Units
V
mV
mV
Ω
µV
p-p
ppm/°C
µSec
mA
0.1KHz≤f
≤10Hz
Note 1
0.1% of V
OUT
Note 2
0.60
15
15
-40
85
-40
85
°C
Rev. 10/11/00
AS4040
ELECTRICAL CHARACTERISTICS (AS4040-5.0V)
Electrical Characteristics at I
IN
= 1000µA, and T
A
= +25°C unless otherwise noted. .
Boldface limits apply over temperature
AS4040A-1
AS4040B-1
AS4040C-1
Parameters
Conditions
Min
Typ
Max
Min
Typ
Max
Min
Typ
Max
Reverse Breakdown
Voltage
Reverse Breakdown
tolerance
Output Impedance
Noise Voltage
Tempco
Turn-on Setting
Operating Current
Range
Temp. Range
I
R
=500
µA
I
R
=500
µA
0.60
0.3
15
30
0.175
15
0.175
5.000
±24
±58
2
0.9
100
30
15
0.175
5.000
±24
±58
2
1.1
150
30
15
5.000
±24
±58
2
1.1
150
Units
V
mV
mV
Ω
µV
p-p
ppm/°C
µSec
mA
0.1KHz≤f
≤10Hz
Note 1
0.1% of V
OUT
Note 2
0.60
0.3
15
0.60
0.3
15
-40
Conditions
I
R
=500
µA
I
R
=500
µA
0.60
15
30
0.175
85
-40
85
-40
85
Parameters
Reverse Breakdown
Voltage
Reverse Breakdown
Tolerance
Output Impedance
Noise Voltage
Tempco
Turn-on Setting
Operating Current
Range
Temp
. Range
AS4040A-2
Min
Typ
Max
5.000
±50
±98
2
50
AS4040B-2
Min
Typ
Max
5.000
±50
±98
2
100
30
AS4040C-2
Min
Typ
Max
5.000
±50
±98
2
150
30
0.175
15
°C
Units
V
mV
mV
Ω
µV
p-p
ppm/°C
µSec
mA
0.1KHz≤f
≤10Hz
Note 1
0.1% of V
OUT
Note 2
0.60
15
0.60
15
15
0.175
15
-40
Conditions
I
R
=500
µA
I
R
=500
µA
0.60
15
30
0.175
85
-40
85
-40
85
Parameters
Reverse Breakdown
Voltage
Reverse Breakdown
Tolerance
Output Impedance
Noise Voltage
Tempco
Turn-on Setting
Operating Current
Range
Temp. Range
Note:
AS4040A-3
Min
Typ
Max
5.000
±100
±148
2
50
AS4040B-3
Min
Typ
Max
5.000
±100
±148
2
100
30
AS4040C-3
Min
Typ
Max
5.000
±100
±148
2
150
30
0.175
15
°C
Units
V
mV
mV
Ω
µV
p-p
ppm/°C
µSec
mA
0.1KHz≤f
≤10Hz
Note 1
0.1% of V
OUT
Note 2
0.60
15
0.60
15
15
0.175
15
-40
85
-40
85
-40
85
°C
1) Three-point measurement guarantees the error band over the specified temperature range.
2) Optimum performance is obtained at currents below 1000
µA.
3) Limits are 100% production tested at 25°C. Limits over temperature are guaranteed through correlation using statistical quality control.
Rev. 10/11/00
AS4040
AS4040 Applications Hints
This device is designed for stable operation and has no need
of an external capacitor between pin 4 and 8. The reference
remains stable if a bypass capacitor is used.
SOT-23
The AS4040 in the SOT-23 package has a parasitic Schottky
diode between pin 3 and pin 1. Pin 1 of SOT-23 must float
or be connected to pin 3.
Conventional Shunt Regulator
In a conventional shunt regulator application (see Figure 1),
an external series resister (R
S
) is connected between the
supply voltage and the AS4040. R
S
determines the current
that flows through the load (I
L
) and the reference(I
Q
). Since
load current and supply voltage may vary, R
S
should be small
enough to supply at least the minimum acceptable I
Q
to the
reference 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
AS4040 is less than 15mA
R
S
is determined by the supply voltage (V
S
), the load and
operating current (I
L
and I
Q
), reference’s reverse breakdown
voltage (V
R
).
Figure 1. AS4040 Fixed
Shunt Regulator Application
V
S
R
S
V
R
AS4040
I
O
+ I
L
I
L
I
Q
V
O
R
S
= (V
S
- V
R
)/(I
L
+I
Q
)
Rev. 10/11/00
AS4040
PACKAGE DRAWING
8-PIN SOIC (S)
4.0 (0.158)
3.8 (0.150)
5.2 (0.205)
4.6 (0.181)
6.2 (0.244)
5.8 (0.228)
Pin 1
1.27 (0.50)
BSC
1.75 (0.069)
1.35 (0.053)
0.78 (0.031)
0.61 (0.024)
5.0 (0.197)
4.8 (0.188)
0.37 (0.015)
BSC
45
°
0.77 (0.030)
0.64 (0.025)
°
(4 PLCS)
7
3
°
-6°
0.56 (0.022)
0.49 (0.019)
0.45 (0.018)
0.35 (0.014)
0.20 (0.008)
0.10 (0.004)
0.22 (0.009)
0.19 (0.007)
7
°
(4 PLCS)
Rev. 10/11/00