1/6
s
ADJUSTABLE OUTPUT VOLTAGE
2.5 to 24V
s
SEVERAL PRECISION @ 25C
2%, 1% and 0.5%
s
SINK CURRENT CAPABILITY
1 to 100mA
s
INDUSTRIAL TEMPERATURE RANGE:
-40 to +105C
s
PERFORMANCES COMPATIBLE WITH
INDUSTRY STANDARD TL431
DESCRIPTION
The TS2431 is a programmable shunt voltage
reference with guaranteed temperature stability
over the entire temperature range of operation
(-40 to +105C). The output voltage may be set to
any value between 2.5V and 24V with an external
resistor bridge.
Available in SOT23-3 surface mount package, it
can be designed in applications where space
saving is a critical issue.
APPLICATION
s
Computers
s
Instrumentation
s
Battery chargers
s
Switch Mode Power Supply
s
Battery operated equipments
ORDER CODE
LT = Tiny Package (SOT23-3) - only available in Tape & Reel (LT)
PIN CONNECTIONS (top view)
Precision
Part Number
in SOT23-3
SOT23
Marking
2%
TS2431ILT
L285
1%
TS2431AILT
L286
0.5%
TS2431BILT
L287
Single temperature range: -40 to +105C
L
SOT23-3L
(Plastic Micropackage)
3
1
2
SOT23-3
Cathode
Reference
Anode
T
S
24
31
TS2431
PROGRAMMABLE SHUNT VOLTAGE REFERENCE
February 2002
TS2431
2/6
ABSOLUTE MAXIMUM RATINGS
OPERATING CONDITIONS
ELECTRICAL CHARACTERISTICS
T
AMBIENT
= 25C (unless otherwise specified)
Symbol
Parameter
Value
Unit
Vka
Cathode to Anode voltage
25
V
I
K
Reverse Breakdown Current
-100 to +150
mA
I
REF
Reference input current range
-0.05 to +10
mA
P
d
Power Dissipation
1)
SOT23-3
360
mW
T
std
Storage Temperature
-65 to +150
C
ESD
Human Body Model (HBM)
2
kV
Machine Model (MM)
200
V
T
LEAD
Lead Temperatue (soldering, 10 seconds)
260
C
1. Pd has been calculated with Tamb = 25C, Tjunction =150C and Rthja = 340C/W for the SOT23-3 package
Symbol
Parameter
Value
Unit
V
KA
Cathode to Anode voltage
V
REF
to 24
V
I
K
Cathode operating current
1)
1 to 100
mA
T
oper
Operating Free Air Temperature Range
-40 to +105
C
1. Maximum power dissipation must be strictly observed to avoid the component destruction.
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
V
REF
Reference input Voltage
V
K
=V
REF
, I
K
=
10
mA
2.5
V
TS2431 (2%)
2.45
2.55
TS2431A (1%)
2.475
2.525
TS2431B (0.5%)
2.488
2.512
|
V
REF
|
Reference input Voltage deviation over
temperature, V
K
=V
REF
, I
K
=
10
mA
(note 1,2)
0C < T < +70C
10
20
mV
-40C < T < +85C
17
30
-40C < T < +105C
20
35
T
C
Temperature coefficient (note 2)
-40C < T < +105C
50
100
ppm/C
I
KMIN
Minimum Operating Current
T = 25C
0.3
0.8
mA
-40C < T < +105C
1
Ratio of change in reference input
voltage to change in cathode to anode
voltage
I
K
=10mA
Vka= 24 to 2.5V
0.3
2
mV/V
I
REF
Reference input current
I
K
=10mA, R1=10K
,
R2=+
(note 3)
T=25C
0.5
2.5
A
-40C < T < +105C
3
|
I
REF
|
Reference input current deviation
I
K
=10mA, R1=10K
,
R2=+
(note 3)
-40C < T < +105C
0.4
1.2
A
I
OFF
Off-state cathode current
V
K
=24V, V
REF
=GND
10
500
nA
|
Z
KA
|
Reverse dynamic impedance
V
K
=V
REF
I
K
=1 to 50mA, f<10kHz
0.5
0.75
E
N
Wide Band Noise
Ik =
10
mA
10Hz < f < 10kHz
300
nV/
Hz
Note 1: Limits are 100% production tested at 25C. Limits over temperature are guaranteed through correlation and by design.
Note 2:
|
V
REF
|
is defined as the difference between the maximum and minimum values of V
REF
obtained over the full temperature range
Note 3: Refer to figure "Test circuit for Vka>Vref" page 4
Vref
Vk
---------------
TS2431
3/6
Reference voltage vs temperature
Cathode voltage vs cathode current
Reference input current vs temperature
Test circuit for Vka = Vref
Cathode voltage vs cathode current
Dynamic impedance vs frequency
-40
-20
0
20
40
60
80
100
2.48
2.49
2.50
2.51
2.52
Ik =10 mA
Vka = Vref
V
o
l
t
ag
e
r
e
f
e
r
e
n
ce (
V
)
Temperature (C)
-0.10
-0.05
0.00
0.05
0.10
-1
0
1
2
3
Vka = Vref
T=25C
V
k
a C
a
t
h
o
d
e
vo
l
t
a
g
e
(
V
)
Ika Cathode current (A)
-40
-20
0
20
40
60
80
100
0.00
0.25
0.50
0.75
1.00
Ik=10mA
R1=10K
R2=+
R
e
f
e
r
e
nc
e
i
npu
t c
u
r
r
e
nt (
A
)
Temperature (C)
Input
Vka
Vref
Ik
Output
0
100
200
300
400
0
1
2
3
T=-40C
T=+25C
T=+105C
Vka = Vref
V
ka C
a
t
h
o
d
e
vo
lt
ag
e (
V
)
Ik Cathode current (A)
10
100
1000
10000
100000
1000000
0
1
2
3
4
5
Vka=Vref
Ik=1mA
T=25C
Z
ka D
y
n
a
m
i
c
im
p
e
d
a
n
ce (
O
h
m
s)
Frequency (Hz)
TS2431
4/6
Off-State current vs temperature
Ratio of change in reference input voltage to
change in Vka voltage vs temperature
Phase and Gain vs frequency
Test circuit for Off-State current measurement
Test circuit for Vka > Vref
Test circuit for phase and gain measurement
-40
-20
0
20
40
60
80
100
0.0
0.1
0.2
0.3
O
f
f-s
ta
te
c
u
r
r
e
n
t
(
A
)
Temperature (C)
-40
-20
0
20
40
60
80
100
0.0
0.1
0.2
0.3
0.4
Vka=24 to 2.5V
Ik=10mA
T=25C
V
r
ef
/
Vk
a
(
m
V/
V
)
Temperature (C)
Vka=24V
Ioff
Input
Ik
Vka = Vref . (1+R1/R2) + Iref . R1
Vka
R1
R2
Iref
Vref
TS2431
5/6
Pulse response at Ik=1mA
Pulse response at Ik = 1mA
Stability boundary conditions
Test circuit for pulse response at Ik = 1mA
Equivalent input noise vs frequency
Block Diagram
0.0
0.5
1.0
1.5
2.0
0
2
4
6
Ik= 0 to 1mA
T=25C
Output voltage
Input voltage
V
o
lt
ag
e (
V
)
Time (s)
0.0
0.5
1.0
1.5
2.0
0
2
4
6
Ik= 1mA to 0
T=25C
Output voltage
Input voltage
V
o
lt
ag
e (
V
)
Time (s)
1E-10
1E-9
1E-8
1E-7
1E-6
1E-5
0
20
40
60
80
100
Stable
area
Instable
area
Vka=5 V
Vka=2.5 V
Vka=3 V
C
a
t
h
o
d
e cu
r
r
e
n
t
(
m
A
)
Capacitive load (F)
Ik=1mA
O
u
t
put
2.5 K
Pulse
Generator
F=100kHz
0 to 5V
In
t
p
u
t
0.1
1
10
100
1000
0
50
100
150
200
250
300
Vka=Vref
Ik=1mA
T=25C
No
ise
(
n
V
/
Hz
)
Frequency (KHz)
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