AN1431T, AN1431M
Surface-mount Adjustable Output Shunt Regulator
s
Overview
The AN1431T and AN1431M are high accuracy stabilized
power supplies in which the output voltage can be adjusted in
the range from approx. 2.5 to 36V by using the external resistor
under the operating temperature. Because of its fast rise charac-
teristics, it can be replaced with Zener diode and has the wide
application range.
AN1431T
5.0±0.2
5.1±0.2
4.0±0.2
Unit : mm
s
Features
•
High precision reference voltage : 2.5V±2%
•
High-temperature stability : 17ppm/˚C typ.
•
Output voltage externally adjustable : 2.5 to 36V
•
Fast rise
•
Low input impedance : 0.2Ω (typ.)
•
Low output noise voltage
0.45
– 0.1
2.54
2.3±0.2
2 3 1
JEDEC : TO-92 (SSIP003-P-0000)
s
Pin Name
〈AN1431T〉
Pin No.
1
2
3
Cathode
Reference pin
Anode
Pin name
AN1431M
5.0±0.2
5.1±0.2
4.0±0.2
13.5±0.5
+0.2
Unit : mm
〈AN1431M〉
Pin No.
1
2
3
Anode
Cathode
2 3 1
Pin name
Reference pin
2.54
0.45
– 0.1
2.3±0.2
+ 0.2
s
Block Diagram
JEDEC : TO-92 (SSIP003-P-0000)
Current
Source
Output Tr
+
Error
Amp.
–
Voltage
Reference
V
KA
= V
REF
(1 +
R
2
= 2.5kΩ
R
1
R
2
) + I
REF
· R
1
1
3
I
K
3
2
1
2
I
REF
V
KA
V
REF
V
1
R
1
R
2
Pin number in
Pin number in
is for the AN1431T.
is for the AN1431M.
13.5±0.5
s
Absolute Maximum Ratings (Ta=25˚C)
Parameter
Supply voltage
Supply current
Power dissipation
Reference input current
Operating ambient
temperature
Storage temperature
AN1431T
AN1431M
AN1431T
AN1431M
Symbol
V
CC
I
CC
P
D
I
REF
V
opr
T
stg
Rating
37
–100 to+150
650 *
– 0.05 to+10
–20 to+85
–25 to+80
–55 to+150
–55 to+125
Unit
V
mA
mW
mA
˚C
˚C
* For the AN1431M, SM to the printed board (glass epoxy of 20
×
20
×
1.7mm with copper film of 1cm
2
)
s
Recommended Operating Range (Ta=25˚C)
Parameter
Operating supply voltage range
Symbol
V
KA
Range
V
REF
(2.5 to 36V)
s
Electrical Characteristics (Ta=25˚C)
Parameter
Reference voltage
Reference voltage temperature deviation
Reference voltage fluctuation
Reference input current
Reference input current temperature deviation
Minimum cathode current
Off-state cathode current
Dynamic impedance
Symbol
V
REF
V
REF (Jev)
*
1
*
2
∆V
REF
∆V
KA
I
REF
I
REF (Jev)
*
2
I
min
I
OFF
|Z
KA
| *
3
Condition
V
KA
=V
REF
, I
K
=10mA
V
KA
=V
REF
, I
K
=10mA,
Ta=0 to+70˚C
I
K
=10mA, DV
KA
=10V to V
REF
I
K
=10mA, DV
KA
=36 to 10V
I
K
=10mA, R
1
=10kΩ, R
2
=
∞
I
K
=10mA, R
1
=10kΩ, R
2
=
∞,
Ta=0 to+70˚C
V
KA
=V
REF
V
KA
=36V, V
REF
=0V
V
KA
=V
REF
, I
K
=1 to 100mA,
f
<
1kHz
=
min
2.45
typ
2.50
3
–1.2
–1
2
0.4
0.4
0.1
0.2
max
2.55
17
–2.7
–2
4
1.2
1.0
1.0
0.5
Unit
V
mV
mV/V
mV/V
µA
µA
mA
µA
Ω
*1
V
REF
V
REF (dev)
= V
REF (max)
–V
REF (min)
The temperature coefficient aV
REF
for the reference input
voltage is equivalently given by the following expression.
V
REF (dev)
V
REF
*
×
10
6
(ppm/˚C)
∆Ta
REF
V
REF (max)
|aV
REF
|=
V
REF (dev)
*
V theat Ta=25˚C;
For example, assuming
following
V
REF (max)
=2500mV (Ta=30˚C),
V
REF (min)
=2497mV (Ta=0˚C),
(V
REF (dev)
=3mV),
V
REF
=2499mV (Ta=25˚C)
∆Ta=70˚C
Then, the following expression is established.
3mV
2499mV
×
10
6
=17.1 (ppm/˚C)
|aV
REF
| =
70˚C
*2 These values are design reference values, not
guaranteed ones.
*3 The dynamic impedance is defined by the following
expression.
|Z
KA
| =
∆V
KA
∆I
K
V
REF (min)
∆Ta
I
REF
I
REF (dev)
= I
REF (max)
– I
REF (min)
I
REF (max)
I
REF (dev)
I
REF (min)
∆Ta
The total dynamic impedance at
∆V
REF
,
∆V
KA
,
I
REF
, and I
REF (dev)
is as follows.
∆V
R
1
|Z| =
∆I
= |Z
KA
| 1 + R
2
s
Power Dissipation
P
D
– Ta
1000
900
Mounting onto Substrate :
20
×
20
×
1.7mm Glass Epoxy
Substrate, Copper Foil 1cm
2
or More
Power Dissipation P
D
(mW)
800
700
600
500
400
300
200
100
0
0
20
40
60
80 100 120 140 160
Ambient Temperature Ta (˚C)
s
Application Circuits
1.Shunt Regulator
+V
V
O
2.Constant Current Power
Supply
+V
I
O
3.Constant Current Source
+V
R
1
V
REF
R
2
AN1431T/M
AN1431T/M
AN1431T/M
R
S
R
S
V
O
= 1+
R
1
V
R
2 REF
I
O
=
V
REF
R
S
I
O
=
V
REF
R
S
I
O
4.Current Boost
+V
V
O
5.Adjustable Output Regulator Combined
with 3-pin Regulator
+V
V
O
AN7805
R
1
R
1
V
REF
R
2
AN1431T/M
C
I
AN1431T/M
V
REF
C
O
R
2
V
O
= 1+
R
1
V
R
2 REF
V
O
= V
REF
1+
R
1
= V
REF
+ 5V
V
R
2 O (min)
s
Characteristics Curve
V
REF
– Ta
2700
2650
2600
2550
2500
2450
2400
2350
–50 –25
4
I
REF
– Ta
Reference Input Current I
REF
(µA)
I
K
=10mA
R
1
=10kΩ
R
2
=
∞
3
V
K
=V
REF
I
K
=10mA
Reference Voltage V
REF
(mV)
2
1
0
25
50
75
100 125
–40 –20
0
20
40
60
80
100
Ambient Temperature Ta (˚C)
Ambient Temperature Ta (˚C)
京公网安备 11010802033920号
EEWORLD
