APL431
Adjustable Precision Shunt Regulator
Features
•
•
•
•
•
•
•
•
Precise Reference Voltage to 2.500V
Guaranteed 0.5%, 1% or 2% Reference
Voltage Tolerance
Sink Current Capability, 1mA to 100mA
Quick Turn-on
Adjustable Output Voltage, V
O
= V
ref
to 20V
Low Operational Cathode Current, 250µA
Typical
0.1Ω Typical Output Impedance
SOT-23, SOT-23-5, SOT-89, SO-8, TO-92
and TO-92S Packages
General Description
The APL431 is a 3-terminal adjustable voltage refer-
ence with specified thermal stability over applicable
commercial temperature ranges. Output voltage may
be set to any value between V
ref
(2.5 V) and 20 V with
two external resistors (see Figure 2). When used
with an photocoupler, the APL431 is an ideal voltage
reference in isolated feedback circuits for 2.5V to 12V
switching-mode power supplies. This device has a
typical output impedance of 0.1Ω. Active output cir-
cuitry provides a very sharp turn-on characteristic,
making the APL431 excellent replacements for ze-
ner diodes in many applications, including on-board
regulation and adjustable power supplies.
NC
ANODE
3
1
2
NC
5
1
2
4
3
Applications
•
•
•
Linear Regulators
Adjustable Power Supply
Switching Power Supply
1
REF
CATHODE
R EF AN O D E C ATH O D E
SOT-23 (Top View)
SOT-23-5 (Top View)
CATHODE
ANODE
2
3
1
2
3
4
8
7
6
5
REF
ANODE
ANODE
NC
Symbol
REF
Anode
Cathode
REF
ANODE CATHODE
ANODE
NC
SOT-89 (Top View)
SO-8 (Top View)
3
CATHODE
Functional Diagram
C athode
3
CATHODE
2
ANODE
2
ANODE
R EF
+
_
1
REF
1
REF
V
ref
TO-92 (Top View)
Anode
TO-92S (Top View)
ANPEC reserves the right to make changes to improve reliability or manufacturability without notice, and advise
customers to obtain the latest version of relevant information to verify before placing orders.
Copyright
ANPEC Electronics Corp.
Rev. C.1 - Jun., 2003
1
www.anpec.com.tw
APL431
Ordering and Marking Information
APL431
L e a d F re e C o d e
H a n d lin g C o d e
Tem p. Range
Package C ode
E le c . G ra d e
E le c . G ra d e
A : 0 .5 % R e fe re n c e V o lta g e T o le ra n c e
B : 1 % R e fe re n c e V o lta g e T o le ra n c e
C : 2 % R e fe re n c e V o lta g e T o le ra n c e
Package C ode
A : S O T -2 3
B : S O T -2 3 -5
D : S O T -8 9
E : T O -9 2
I : T O -9 2 S
K : S O -8
Y : C h ip F o rm
Tem p. Range
C : 0 to 7 0
°
C
I : -4 0 to 8 5
°
C
H a n d lin g C o d e
P B : P la s tic B a g
TB : Tape & Box
TR : Tape & Reel
L e a d F re e C o d e
L : L e a d F re e D e v ic e
B l a n k : O r g in a l D e v i c e
A P L 4 3 1 E /I :
APL
431
XXXXX
X X X X X - D a te C o d e
A P L 4 3 1 A /B :
431
A P L 4 3 1 D /K :
AP L431
XXXXX
XXXXX
- D a te C o d e
Absolute Maximum Ratings
Symbol
V
KA
I
K
I
REF
θ
JA
Parameter
Cathode voltage
Continuous cathode current range
Reference current range
Thermal Resistance from Junction to Ambient in Free Air
SOT-23
SOT-23-5
SOT-89
TO-92
SO-8
Ambient temperature range
APL431XXC
APL431XXI
Junction temperature range
APL431XXC
APL431XXI
Storage Temperature Range
Lead temperature range, T
s
(Soldering, 10sec)
Original Device
Lead Free Device
Rating
20
100
3
416
357
250
250
210
0 to 70
-40 to 85
0 to 150
-40 to 150
-65 to 150
260
300
Unit
V
mA
mA
°C/W
T
A
T
j
T
STG
T
SOL
°C
°C
°C
°C
Copyright
ANPEC Electronics Corp.
Rev. C.1 - Jun., 2003
2
www.anpec.com.tw
APL431
Electrical Characteristics (Cont.)
Symbol
Parameter
T
A
= 25°C ( unless otherwise noted)
APL431
Min.
2.487
2.475
2.450
Typ.
2.500
2.500
2.500
Max.
2.513
2.525
2.550
20
30
-3
-2.5
3
1
0.5
1
0.4
100
Test Conditions
V
KA
=V
REF
,
I
K
=10mA*
1
Unit
V
REF
∆
V
REF
/ T
∆
V
REF
/
∆
V
KA
I
REF
∆
I
REF
/T
I
K(min)
I
K(off)
|Z
KA
|
I
K
APL431A
Reference voltage
APL431B
APL431C
V
KA
=V
REF
,I
K
=10mA
Reference voltage
T
A
=0 to 70°C*
1
drift over temp. range
T
A
=-40 to 85°C*
1
I
K
=10mA, V
KA
=V
REF
to 10V
*2
Voltage ratio (open
loop gain)
I
K
=10mA, V
KA
=V
REF
to 20V
*2
I
K
=10mA,
Reference current
R
1
=10k
Ω
, R
2
=open
*2
I
K
=10mA, R
1
=10k
Ω
,
Reference current
drift
R
2
=open, T
A
= -40 to 85
°
C
*2
Min. cathode current V
KA
=V
REF*1
Off-state cathode
V
KA
= 20V, V
REF
= 0V
*3
current
V
KA
=V
REF
Dynamic impedance
I
K
=1mA to 100mA, f
≤
1kHz
*1
Cathode current
V
KA
=V
REF
+ 50mV
*2
V
mV
mV/V
µ
A
µ
A
mA
µ
A
Ω
mA
-1.5
-1.2
1.0
0.3
0.25
0.1
0.1
Notes :
*1 : use Figure 1
*2 : use Figure 2
*3 : use Figure 3
Copyright
ANPEC Electronics Corp.
Rev. C.1 - Jun., 2003
3
www.anpec.com.tw
APL431
Test figures
V
IN
I
K
V
REF
V
o
V
IN
I
K(off)
V
o
Figure 1. Test Circuit for V
KA
=V
REF
, V
O
=V
KA
=V
REF
Figure 3. Test Circuit for I
K(off)
V
IN
I
K
R1
R2
I
REF
V
REF
V
o
Figure 2. Test Circuit for V
KA
>V
REF
,
V
O
= V
KA
= V
REF
×
(1+R
1
/R
2
) + I
REF
×
R
1
Application schematic
5-Volt Precision Regulator
V
IN
R
b
V
o
27.5kΩ
0.1%
27.5kΩ
0.1%
∗
R
b
should provide cathode current large than
1mA to maintain APL431 work properly.
Copyright
ANPEC Electronics Corp.
Rev. C.1 - Jun., 2003
4
www.anpec.com.tw
APL431
Typical Characteristics
Reference Input Current vs. Temperature
2
Cathode Current vs. Cathode Voltage
800
Reference Input Current (µA)
600
Cathode Current (µA)
1.5
400
1
200
I
K-MIN
0.5
0
0
-40
-20
0
20
40
60
80
100
-2 0 0
-1
0
1
2
3
Temperature (°C)
Cathode Voltage (V)
Cathode Current vs. Cathode Voltage
800
Reference Voltage vs. Temperature
2.52
2.515
Cathode Current (mA)
Reference Voltage (V)
-1
0
1
2
3
600
2.51
2.505
2.5
2.495
2.49
2.485
2.48
2.475
400
200
0
-200
2.47
-40
-20
0
20
40
60
80
100
Cathode Voltage (V)
Temperature (°C)
Copyright
ANPEC Electronics Corp.
Rev. C.1 - Jun., 2003
5
www.anpec.com.tw
