TL431A Datasheet, PDF (4/5 Pages) Unisonic Technologies – PROGRAMMABLE PRECISION REFERENCE

UTC TL431A LINEAR INTEGRATED CIRCUIT
TEST CIRCUIT
INPUT
VKA
IKA
VREF
UTC TL431A
INPUT
R1
IREF
R2 ^VREF
VKA
IKA
UTC TL431A
INPUT
VKA
IKA(OFF)
UTC TL431A
Fig 7 Test Circuit For VKA=VREF
VKA=VREF*(1+R1/R2)+IREF*R1
Fig 8 Test Circuit for VKA >= VREF
Fig 9 Test Circuit For IKA(OFF)
APPLICATION CIRCUIT
Vi
Vo
R1
VREF
R2
UTC TL431A
Vo=(1+R1/R2)*VREF
Fig 10 Shutdown Regulator
Vi
IN
UTC7805 ^OUT
Vo
COMMON
R1
VREF
R2
UTC TL431A
Vo=(1+R1/R2)*VREF
Fig 11 Output Control of a Three
-Terminal Fixed Regulator
Vi
Io _Vo
Vi
Rs
Vi
Vo
R1
VREF
R2
UTC TL431A
Vo=(1+R1/R2)*VREF
Fig 12 Higher-current Shunt Regulator
Io
Vo
RCL
UTC TL431A
Rs
IO=VREF/RS
Fig 13 Constant-current Sink
UTC TL431A
RS=VREF/RCL
Fig 14 Current Limiting or Current Source
UTC UNISONIC TECHNOLOGIES CO., LTD.
4
QW-R103-007,D