TS431BCYRM - Taiwan Semiconductor Co., Ltd.

TS431

Adjustable Precision Shunt Regulator

1/13 Version: F07

TO-92

SOT-89

SOT-23

SOP-8

General Description

TS431 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 TS431 series operates as a shunt

regulator, it can be used as either a positive or negative stage reference.

Features

● Precision Reference Voltage

TS431 – 2.495V ±2%

TS431A – 2.495V ±1%

TS431B – 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

Block Diagram

Ordering Information

Part No.

Package

Packing

TS431xCT B0

TO-92

1Kpcs / Bulk

TS431xCT B0G

TO-92

1Kpcs / Bulk

TS431xCT A3

TO-92

2Kpcs / Ammo

TS431xCT A3G

TO-92

2Kpcs / Ammo

TS431xCX RF

SOT-23

3Kpcs / 7” Reel

TS431xCX RFG

SOT-23

3Kpcs / 7” Reel

TS431xCY RM

SOT-89

1Kpcs / 7” Reel

TS431xCY RMG

SOT-89

1Kpcs / 7” Reel

TS431xCS RL

SOP-8

2.5Kpcs / 13” Reel

TS431xCS RLG

SOP-8

2.5Kpcs / 13” Reel

Note: Where xx denotes voltage tolerance

Blank: ±2%, A: ±1%, B: ±0.5%

“G” denotes for Halogen free products

Absolute Maximum Rating (Ta = 25oC unless otherwise noted)

Parameter

Symbol

Limit

Unit

Cathode Voltage (Note 1)

VKA

37

V

Continuous Cathode Current Range

IK

-100 ~ +150

mA

Reference Input Current Range

IREF

-0.05 ~ +10

mA

TO-92

0.625

SOT-23

0.30

Power Dissipation

SOT-89 / SOP-8

PD

0.50

W

Junction Temperature

TJ

+150

oC

Operating Temperature Range

TOPER

0 ~ +70

oC

Storage Temperature Range

TSTG

-65 ~ +150

oC

Note 1: Voltage values are with respect to the anode terminal unless otherwise noted.

Pin Definition:

1. Reference

2. Cathode

3. Anode

Pin Definition:

1. Cathode

8. Reference

2. Anode

7. Anode

3. Anode

6. Anode

4. N/C

5. N/C

Pin Definition:

1. Reference

2. Anode

3. Cathode

TS431

Adjustable Precision Shunt Regulator

2/13 Version: F07

Recommend Operating Condition

Parameter

Symbol

Limit

Unit

Cathode Voltage (Note 1)

VKA

Ref ~ 36

V

Continuous Cathode Current Range

IK

1 ~ 100

mA

Recommend Operating Condition

Parameter

Symbol

Test Conditions

Min

Typ

Max

Unit

TS431

2.446

2.550

TS431A

2.470

2.520

Reference voltage

TS431B

VREF

VKA =VREF, IK =10mA (Figure 1)

Ta=25oC

2.483

2.495

2.507

V

Deviation of reference input

voltage

∆ VREF

VKA = VREF, IK =10mA (Figure 1)

Ta= full range

--

3

17

mV

Radio of change in Vref to

change in cathode Voltage

∆VREF

/∆VKA

IKA =10mA, VKA = 10V to VREF

VKA = 36V to 10V (Figure 2)

--

-1.4

-1.0

-2.7

-2.0

mV/V

Reference Input current

IREF

R1=10KΩ, R2=

∞

, IKA =10mA

Ta= full range (Figure 2)

--

0.7

4.0

uA

Deviation of reference input

current, over temp.

∆IREF

R1=10KΩ, R2=

∞

, IKA =10mA

Ta= full range (Figure 2)

--

0.4

1.2

uA

VREF =0V (Figure 3), VKA =36V

--

1.0

uA

Off-state Cathode Current

IKA (off)

VREF =0V (Figure 3), VKA =36V

TJ=-25ºC~125ºC

(Value is defined by design)

--

30

uA

Dynamic Output Impedance

| ZKA |

f<1KHz, VKA = VREF

IKA =1mA to 100mA (Figure 1)

--

0.22

0.5

Ω

Minimum operating cathode

current

IKA (min)

VKA = VREF (Figure 1)

--

0.4

0.6

mA

* 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.

Example: Maximum VREF=2.496V at 30oC, minimum VREF =2.492V at 0oC, VREF =2.495V at 25oC, ΔT=70oC

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)

TS431

Adjustable Precision Shunt Regulator

3/13 Version: F07

Test Circuits

Figure 1: VKA = VREF

Figure 2: VKA > VREF

Figure 3: Off-State Current

Additional Information – Stability

When The TS431/431A/431B 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 TS431/431A/431B exhibits instability with capacitances in the range of 10nF to 1uF (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 0.1uF 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 (10uF) 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 TS431/431A/431B is located right at the load, so the load decoupling capacitor is directly across it, then this capacitor

will have to be ≤1nF or ≥10uF.

Applications Examples

Figure 4: Voltage Monitor

Figure 5: Output Control for Three Terminal

Fixed Regulator

TS431

Adjustable Precision Shunt Regulator

4/13 Version: F07

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

TS431

Adjustable Precision Shunt Regulator

5/13 Version: F07

Applications Examples (Continue)

Vin

Vout

<Vref

V+

>Vref

≈0.74V

Figure 12: Single-Supply Comparator with

Temperature-Compensated Threshold

Figure 13: Constant Current Sink

Figure 14: Delay Timer

TS431

Adjustable Precision Shunt Regulator

6/13 Version: F07

Typical Performance Characteristics

Test Circuit for Voltage Amplification

Figure 14: Small-Signal Voltage Gain and Phase Shirt vs. Frequency

Test Circuit for Reference Impedance

Figure 15: Reference Impedance vs. Frequency

TS431

Adjustable Precision Shunt Regulator

7/13 Version: F07

Typical Performance Characteristics (Continue)

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 A

Test Circuit for Curve B, C and D

Figure 16: Stability Boundary Condition

Test Circuit for Pulse Response, Ik=1mA

Figure 17: Pulse Response

TS431

Adjustable Precision Shunt Regulator

8/13 Version: F07

Electrical Characteristics

Figure 18: Reference Voltage vs. Temperature

Figure 19: Reference Current vs. Temperature

Figure 20: Cathode Current vs. Cathode Voltage

TS431

Adjustable Precision Shunt Regulator

9/13 Version: F07

TO-92 Mechanical Drawing

Marking Diagram

X

= Tolerance Code

(A = ±1%, B = ±0.5%, C = ±0.25%, Blank = ±2%,)

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

TO-92 DIMENSION

MILLIMETERS

INCHES

DIM

MIN

MAX

MIN

MAX

A

4.30

4.70

0.169

0.185

B

4.30

4.70

0.169

0.185

C

13.53 (typ)

0.532 (typ)

D

0.39

0.49

0.015

0.019

E

1.18

1.28

0.046

0.050

F

3.30

3.70

0.130

0.146

G

1.27

1.31

0.050

0.051

H

0.33

0.43

0.013

0.017

TS431

Adjustable Precision Shunt Regulator

10/13 Version: F07

SOT-23 Mechanical Drawing

Marking Diagram

1

= Device Code

X

= Tolerance Code

(A = ±1%, B = ±0.5%, C = ±0.25%, Blank = ±2%,)

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

SOT-23 DIMENSION

MILLIMETERS

INCHES

DIM

MIN

MAX

MIN

MAX.

A

0.95 BSC

0.037 BSC

A1

1.9 BSC

0.074 BSC

B

2.60

3.00

0.102

0.118

C

1.40

1.70

0.055

0.067

D

2.80

3.10

0.110

0.122

E

1.00

1.30

0.039

0.051

F

0.00

0.10

0.000

0.004

G

0.35

0.50

0.014

0.020

H

0.10

0.20

0.004

0.008

I

0.30

0.60

0.012

0.024

J

5º

10º

5º

10º

TS431

Adjustable Precision Shunt Regulator

11/13 Version: F07

SOT-89 Mechanical Drawing

Marking Diagram

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

CY

= Package Code

SOT-89 DIMENSION

MILLIMETERS

INCHES

DIM

MIN

MAX

MIN

MAX

A

4.40

4.60

0.173

0.181

B

1.50

1.7

0.059

0.070

C

2.30

2.60

0.090

0.102

D

0.40

0.52

0.016

0.020

E

1.50

0.059

F

3.00

0.118

G

0.89

1.20

0.035

0.047

H

4.05

4.25

0.159

0.167

I

1.4

1.6

0.055

0.068

J

0.35

0.44

0.014

0.017

TS431

Adjustable Precision Shunt Regulator

12/13 Version: F07

SOP-8 Mechanical Drawing

Marking Diagram

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

SOP-8 DIMENSION

MILLIMETERS

INCHES

DIM

MIN

MAX

MIN

MAX.

A

4.80

5.00

0.189

0.196

B

3.80

4.00

0.150

0.157

C

1.35

1.75

0.054

0.068

D

0.35

0.49

0.014

0.019

F

0.40

1.25

0.016

0.049

G

1.27BSC

0.05BSC

K

0.10

0.25

0.004

0.009

M

0º

7º

0º

7º

P

5.80

6.20

0.229

0.244

R

0.25

0.50

0.010

0.019

TS431

Adjustable Precision Shunt Regulator

13/13 Version: F07

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.