UTC TL431L
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
1
QW-R103-014,D
PROGRAMMABLE PRECISION
REFERENCE
DESCRIPTION
The UTC TL431L is a three-terminal adjustable regulator
with a guaranteed thermal stability over applicable
temperature ranges. The output voltage may be set to any
value between Vref(approximately 2.5V) and 20V with two
external resistors. It provides very wide applications,
including shunt regulator, series regulator, switching
regulator, voltage reference and others.
FEATURES
*Programmable output Voltage to 20V.
*Low dynamic output impedance 0.2
.
*Sink current capability of 1.0 to 100mA.
*Equivalent full-range temperature coefficient of 50ppm/
C
typical for operation over full rated operating temperature
range.
TO-92
1
SOP-8
SOT-89
1
1
SOT-25
SOT-23
1
3
2
2
3
5
4
MSOP-8
SOP-8 1: Cathode; 2,3,6,7: Anode
8: Ref. ; 4,5: N/C
MSOP-8 1: Cathode ; 6: Anode ; 8: Ref.
2,3,4,5,7: N/C
TO-92 1: Ref. ; 2: Anode ; 3: Cathode
SOT-89 1: Ref. ; 2: Anode ; 3: Cathode
SOT-23 1: Cathode; 2: Ref. ; 3: Anode
SOT-25 1,2: N/C; 3: Cathode; 4: Ref.; 5: Anode
BLOCK DIAGRAM
2.5V Vref
CATHODE
ANODE
REFERENCE
CATHODE
(K)
ANODE(A)
REFERENCE
(R)
UTC TL431L
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
2
QW-R103-014,D
ABSOLUTE MAXIMUM RATINGS
(Operating temperature range applies unless otherwise specified))
PARAMETER SYMBOL
VALUE
UNIT
Cathode Voltage
V
KA
20 V
Cathode Current Range (Continuous)
I
KA
-100 ~ +150
mA
Reference Input Current Range
Iref
-0.05 ~ +10
mA
Operating Junction Temperature
Tj
150
C
Operating Ambient Temperature
Topr
0 ~ +70
C
Storage Temperature
Tstg
-65 ~ +150
C
RECOMMENDED OPERATING CONDITIONS
PARAMETER SYMBOL MIN
TYP
MAX
UNIT
Cathode Voltage
V
KA
V
REF
20 V
Cathode Current
I
KA
1
100 mA
ELECTRICAL CHARACTERISTICS
(Ta=25
C, unless otherwise specified)
PARAMETER SYMBOL
TEST
CONDITIONS
MIN
TYP
MAX
UNIT
Reference Input Voltage
Vref
V
KA
=V
REF
,I
KA
=10mA
2.450 2.50 2.550 V
Deviation of reference Input Voltage
Over temperature (note 1)
Vref/T V
KA
=V
REF
,I
KA
=10mA
T
MIN
<=T
A<=
T
MAX
4.5 17 mV
Ratio of Change in Reference Input
Voltage to the Change in Cathode
Voltage
Vref /V
KA
I
KA
=10mA
V
KA
=10V~V
REF
V
KA
=20V~10V
-1.0
-0.5
-2.7
-2.0
mV/V
Reference Input Current
Iref
I
KA
=10mA,R1=10k
,R2=
1.5
4
A
Deviation of Reference Input Current
Over Full Temperature Range
Iref/T I
KA
=10mA,R1=10k
,R2=
T
A
=full Temperature
0.4 1.2
A
Minimum Cathode Current for
Regulation
I
KA
(min) V
KA
=V
REF
0.45 1.0 mA
Off-State Cathode Current
I
KA
(OFF) V
KA
=20V, V
REF
=0
0.05
1.0
A
Dynamic Impedance
Z
KA
V
KA
=V
REF
,I
KA
=1 to 100mA
f
1.0kHz
0.15 0.5
Note:T
MIN
=0
C,T
MAX
=+70
C
Remark: Reference voltage of
1% tolerance is also available per customer's request.
UTC TL431L
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
3
QW-R103-014,D
TYPICAL PERFORMANCE CHARACTERISTICS
-2
-1
0
1
2
3
-100
-75
-50
-25
0
25
50
75
100
125
Cathode Voltage (V)
Cathode Current (mA)
Fig 1 Cathode Current Vs Cathode Voltage
Ta=25
V
KA
=V
REF
-1
1
0
2
3
-200
0
400
200
600
800
-2
Cathode Voltage (V)
Cathode Current (
m
A)
Fig 2 Cathode Current Vs Cathode Voltage
I
KA(min)
0
5
10
15
20
25
30
35
40
0
-5
-10
-15
-20
-25
-30
-35
-40
Cathode Voltage (V)
Change In Reference INput
Voltage (mV)
Fig 3 Change in Reference Input Voltage
Vs Cathode voltage
I
KA
=100mA
Ta=25
0
1
2
3
4
5
6
7
0
1
2
3
4
5
6
7
Time ( s)
Input and Output Voltage (V)
Fig 4 Pulse Response
Ta=25
2
10
1
10
-1
10
0
10
7
10
6
10
5
10
10
4
10
3
Impedance (
)?
Frequency (Hz)
Fig 5 Dynamic Impedance
Vs Frequency
Ta=25
I
KA
=0mA to 100mA
-10
0
10
20
30
40
50
60
70
7
10
6
10
5
10
10
4
10
3
Fig 6 Small Signal Voltage Amplification Vs Frequency
Voltage Amplification (dB)
Frequency (Hz)
Ta=25
I
KA
=10mA
Ta=25
V
KA
=V
REF
UTC TL431L
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
4
QW-R103-014,D
TEST CIRCUIT
INPUT
V
KA
V
REF
I
KA
UTC TL431L
R1
R2
I
REF
V
KA=
V
REF*(
1
+
R1
/
R2
)+
I
REF*
R1
INPUT
V
KA
V
REF
I
KA
UTC TL431L
INPUT
V
KA
I
KA(OFF)
UTC TL431L
Fig 7 Test Circuit For V
KA
=V
REF
Fig 8 Test Circuit for V
KA >=
V
REF
Fig 9 Test Circuit For I
KA(OFF)
APPLICATION CIRCUIT
Vi
Vo
V
REF
UTC TL431L
R1
R2
Vo=(1+R1/R2)*V
REF
Vi
Vo
V
REF
UTC TL431L
R1
R2
Vo=(1+R1/R2)*V
REF
UTC7805
OUT
IN
COMMON
Vi
Vo
V
REF
UTC TL431L
R1
R2
Vo=(1+R1/R2)*V
REF
Fig 10 Shutdown Regulator Fig 11 Output Control of a Three Fig 12 Higher-current Shunt Regulator
-Terminal Fixed Regulator
Vi
Vo
UTC TL431L
Rs
R
S
=V
REF
/RCL
RCL
Io
Vi
Vo
UTC TL431L
Rs
Io
I
O
=V
REF
/R
S
Fig 13 Constant-current Sink Fig 14 Current Limiting or Current Source
UTC TL431L
LINEAR INTEGRATED CIRCUIT
UTC
UNISONIC TECHNOLOGIES CO., LTD.
5
QW-R103-014,D
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
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