TS1431 - Taiwan Semi

TS1431
Adjustable Precision Shunt Regulator
SOT-23
Pin Definition:
1. Cathode
2. Reference
3. Anode
General Description
TS1431 series integrated circuits are three-terminal programmable shunt regulator diodes. These monolithic IC voltage
references operate as a low temperature coefficient zener which is programmable from VREF to 36 volts with two
external resistors. These devices exhibit a wide operating current range of 1.0 to 100mA with a typical dynamic
impedance of 0.22Ω. The characteristics of these references make them excellent replacements for zener diodes in
many applications such as digital voltmeters, power supplies, and op amp circuitry. The 2.5V reference makes it
convenient to obtain a stable reference from 5.0V logic supplies, and since The TS1431 series operates as a shunt
regulator, it can be used as either a positive or negative stage reference.
Features
●
Ordering Information
Precision Reference Voltage
Part No.
TS1431A – 2.495V±1%
TS1431xCX RF
TS1431B – 2.495V±0.5%
●
Equivalent Full Range Temp. Coefficient: 50ppm/ ºC
●
Programmable Output Voltage up to 36V
●
Fast Turn-On Response
●
Sink Current Capability of 1~100mA
●
Low Dynamic Output Impedance: 0.2Ω
●
Low Output Noise
Application
●
Voltage Monitor
●
Delay Timmer
●
Constant –Current Source/Sink
●
High-Current Shunt Regulator
●
Crow Bar
●
Over-Voltage / Under-Voltage Protection
Package
Packing
SOT-23
3kpcs / 7” Reel
TS1431xCX RFG
SOT-23
3kpcs / 7” Reel
Note: “G” denote for Green Product
Where xx denotes voltage tolerance
A: ±1%, B: ±0.5%
Block Diagram
Absolute Maximum Ratings (TA = 25oC unless otherwise noted)
Parameter
Symbol
Limit
Unit
Cathode Voltage
VKA
36
V
Continuous Cathode Current Range
IKA
1 ~ +100
mA
Reference Input Current Range
IREF
-0.05 ~ +10
mA
Power Dissipation
PD
0.30
W
+150
o
C
0 ~ +70
o
C
-65 ~ +150
o
C
Junction Temperature
TJ
Operating Temperature Range
TOPR
Storage Temperature Range
TSTG
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Version: D14
TS1431
Adjustable Precision Shunt Regulator
Recommended Operating Condition
Parameter
Cathode Voltage
(Note 1)
Symbol
Limit
Unit
VKA
Ref ~ 36
V
IK
1 ~ 100
mA
Continuous Cathode Current Range
Electrical Characteristics
Parameter
Reference voltage
Symbol
TS1431A
TS1431B
Deviation of reference input
voltage
Radio of change in Vref to
change in cathode Voltage
Reference Input current
Deviation of reference input
current, over temp.
Off-state Cathode Current
Dynamic Output Impedance
VREF
∆ VREF
∆VREF /∆VKA
IREF
∆IREF
IKA (off)
| ZKA |
Test Conditions
VKA =VREF, IK =10mA (Figure 1)
o
TA=25 C
VKA = VREF, IK =10mA (Figure 1)
Min
2.475
2.487
Typ
2.495
Max
Unit
2.525
V
2.513
--
3
17
IKA =10mA, VKA = 10V to VREF
--
-1.4
-2.7
VKA = 36V to 10V (Figure 2)
--
-1.0
-2.0
--
0.7
4.0
µA
--
0.4
1.2
µA
--
--
1.0
µA
--
0.22
0.5
Ω
TA= full range
R1=10KΩ, R2= ∞ , IKA =10mA
TA = full range (Figure 2)
R1=10KΩ, R2= ∞ , IKA =10mA
TA = full range (Figure 2)
VREF =0V (Figure 3),
VKA =36V
f<1KHz, VKA = VREF
IKA =1mA to 100mA (Figure 1)
mV
mV/V
Minimum operating cathode
IKA (min)
VKA = VREF (Figure 1)
-0.4
0.6
mA
current
* The deviation parameters ∆VREF and ∆IREF are defined as difference between the maximum value and minimum value
obtained over the full operating ambient temperature range that applied.
* The average temperature coefficient of the
reference input voltage, αVREF is defined as:
Where: T2-T1 = full temperature change.
αVREF can be positive or negative depending on whether the slope is positive or negative.
o
o
o
o
Example: Maximum VREF=2.496V at 30 C, minimum VREF =2.492V at 0 C, VREF =2.495V at 25 C, ΔT=70 C
αVREF | = [4mV / 2495mV] * 106 / 70oC ≈ 23ppm/oC
Because minimum VREF occurs at the lower temperature, the coefficient is positive.
* The dynamic impedance ZKA is defined as:
| ZKA | = ΔVKA / ΔIKA
* When the device operating with two external resistors, R1 and R2, (refer to Figure 2) the total dynamic impedance of
the circuit is given by:
| ZKA | = Δv / Δi | ≈ ZKA | * ( 1 + R1 / R2)
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Version: D14
TS1431
Adjustable Precision Shunt Regulator
Test Circuits
Figure 1: VKA = VREF
Figure 2: VKA > VREF
Figure 3: Off-State Current
Additional Information – Stability
When The TS1431A/1431B is used as a shunt regulator, there are two options for selection of CL, are recommended
for optional stability:
A) No load capacitance across the device, decouple at the load.
B) Large capacitance across the device, optional decoupling at the load.
The reason for this is that TS1431A/1431B exhibits instability with capacitances in the range of 10nF to 1µF (approx.)
at light cathode current up to 3mA(typ). The device is less stable the lower the cathode voltage has been set for.
Therefore while the device will be perfectly stable operating at a cathode current of 10mA (approx.) with a 0.1µF
capacitor across it, it will oscillate transiently during start up as the cathode current passes through the instability region.
Select a very low capacitance, or alternatively a high capacitance (10µF) will avoid this issue altogether. Since the user
will probably wish to have local decoupling at the load anyway, the most cost effective method is to use no capacitance
at all directly across the device. PCB trace/via resistance and inductance prevent the local load decoupling from
causing the oscillation during the transient start up phase.
Note: if the TS1431A/1431B is located right at the load, so the load decoupling capacitor is directly across it, then this
capacitor will have to be ≤1nF or ≥10µF.
Applications Examples
Figure 5: Output Control for Three Terminal
Fixed Regulator
Figure 4: Voltage Monitor
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TS1431
Adjustable Precision Shunt Regulator
Applications Examples (Continue)
Figure 6: Shunt Regulator
Figure 7: High Current Shunt Regulator
Figure 8: Series Pass Regulator
Figure 9: Constant Current Source
Figure 10: TRIAC Crowbar
Figure 11: SCR Crowbar
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Version: D14
TS1431
Adjustable Precision Shunt Regulator
Applications Examples (Continue)
Vin
<Vref
>Vref
Vout
V+
≈0.74V
Figure 12: Single-Supply Comparator with
Temperature-Compensated Threshold
Figure 13: Constant Current Sink
Figure 14: Delay Timer
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TS1431
Adjustable Precision Shunt Regulator
Typical Performance Characteristics
Test Circuit for Voltage Amplification
Figure 15: Small-Signal Voltage Gain and Phase Shirt vs. Frequency
Test Circuit for Reference Impedance
Figure 16: Reference Impedance vs. Frequency
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Adjustable Precision Shunt Regulator
Typical Performance Characteristics (Continue)
Test Circuit for Curve A
The areas under the curves represent conditions that may
cause the device to oscillate. For curves B, C, and D, R2
and V+ were adjusted to establish the initial VKA and IKA
conditions with CL=0. VBATT and CL then were adjusted to
determine the ranges of stability.
Test Circuit for Curve B, C and D
Figure 17: Stability Boundary Condition
Test Circuit for Pulse Response, Ik=1mA
Figure 18: Pulse Response
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TS1431
Adjustable Precision Shunt Regulator
Electrical Characteristics
Figure 19: Reference Voltage vs. Temperature
Figure 20: Reference Current vs. Temperature
Figure 21: Cathode Current vs. Cathode Voltage
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Version: D14
TS1431
Adjustable Precision Shunt Regulator
SOT-23 Mechanical Drawing
Unit: Millimeters
Marking Diagram
1 = Device Code
X = Tolerance Code
(A = ±1%, B = ±0.5%)
Y = Year Code
M = Month Code
(A=Jan, B=Feb, C=Mar, D=Apl, E=May, F=Jun, G=Jul, H=Aug, I=Sep,
J=Oct, K=Nov, L=Dec)
= Month Code for Halogen Free Product
(O=Jan, P=Feb, Q=Mar, R=Apl, S=May, T=Jun, U=Jul, V=Aug, W=Sep,
X=Oct, Y=Nov, Z=Dec)
L = Lot Code
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Version: D14
TS1431
Adjustable Precision Shunt Regulator
Notice
Specifications of the products displayed herein are subject to change without notice. TSC or anyone on its behalf,
assumes no responsibility or liability for any errors or inaccuracies.
Information contained herein is intended to provide a product description only. No license, express or implied, to any
intellectual property rights is granted by this document. Except as provided in TSC’s terms and conditions of sale for
such products, TSC assumes no liability whatsoever, and disclaims any express or implied warranty, relating to sale
and/or use of TSC products including liability or warranties relating to fitness for a particular purpose, merchantability,
or infringement of any patent, copyright, or other intellectual property right.
The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications. Customers
using or selling these products for use in such applications do so at their own risk and agree to fully indemnify TSC for
any damages resulting from such improper use or sale.
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Version: D14