Datasheet TL 431 CD SMD Datasheet (FREI)

TL431, A, B Series, NCV431A, B

Programmable Precision References

The TL431, A, B 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 V devices exhibit a wide operating current range of 1.0mA to 100 mA with a typical dynamic impedance of 0.22 W. 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 2.5 V reference makes it convenient to obtain a stable reference from 5.0 V logic supplies, and since the TL431, A, B operates as a shunt regulator, it can be used as either a positive or negative voltage reference.

Features

•Programmable Output Voltage to 36 V

•Voltage Reference Tolerance: ±0.4%, Typ @ 25°C (TL431B)

•Low Dynamic Output Impedance, 0.22 W Typical

•Sink Current Capability of 1.0 mA to 100 mA

•Equivalent Full- Range Temperature Coefficient of 50 ppm/°C Typical

•Temperature Compensated for Operation over Full Rated Operating

Temperature Range

•Low Output Noise Voltage

•Pb-Free Packages are Available

to 36 V with two external resistors. These

ref

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TO-92 (TO-226)

LP SUFFIX

CASE 29

2

3

1

8

Cathode

Pin 1. Reference

2. Anode

3. Cathode

1

2

N/C

3

N/C

4

N/C

(Top View)

PDIP-8

P SUFFIX

CASE 626

Micro8E DM SUFFIX CASE 846A

8

Reference

7

N/C

6

Anode

5

N/C

1

8

© Semiconductor Components Industries, LLC, 2007

June, 2007 - Rev. 27

SOIC-8

8

1

Cathode

N/C

2

3

4

(Top View)

Anode Anode

This is an internally modified SOIC-8 package. Pins 2, 3, 6 and 7 are electrically common to the die attach flag. This internal lead frame modification increases power dissipation capability when appropriately mounted on a printed circuit board. This modified package conforms to all external dimensions of the standard SOIC-8 package.

D SUFFIX CASE 751

8

Reference

7

6

5

N/C

ORDERING INFORMATION

See detailed ordering and shipping information in the package dimensions section on page 13 of this data sheet.

DEVICE MARKING INFORMATION

See general marking information in the device marking section on page 16 of this data sheet.

1 Publication Order Number:

TL431/D

TL431, A, B Series, NCV431A, B

Symbol

Representative Schematic Diagram

Component values are nominal

Cathode

Reference

(R)

Representative Block Diagram

Reference

(R)

2.5 V

+

-

ref

(K)

Anode

(A)

Anode (A)

Cathode

(K)

Reference

(R)

3.28 k

2.4 k 7.2 k

20 pF

800

Cathode (K)

800

20 pF

150

4.0 k

10 k

1.0 k

Anode (A)

This device contains 12 active transistors.

MAXIMUM RATINGS (Full operating ambient temperature range applies, unless otherwise noted.)

Rating

Cathode to Anode Voltage V

Cathode Current Range, Continuous I

Reference Input Current Range, Continuous I

Operating Junction Temperature T

Operating Ambient Temperature Range

TL431I, TL431AI, TL431BI -40 to +85 TL431C, TL431AC, TL431BC 0 to +70 NCV431AI, NCV431B, TL431BV -40 to +125

Storage Temperature Range T

Total Power Dissipation @ TA = 25°C P

Derate above 25°C Ambient Temperature D, LP Suffix Plastic Package 0.70 P Suffix Plastic Package 1.10 DM Suffix Plastic Package 0.52

Total Power Dissipation @ TC = 25°C P

Derate above 25°C Case Temperature D, LP Suffix Plastic Package 1.5 P Suffix Plastic Package 3.0

ESD Rating HBM

Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability.

Symbol Value Unit

37 V

-100 to +150 mA

-0.05 to +10 mA

150 °C

°C

-65 to +150 °C

W

>2000

V

>200

ref

T

stg

MM

KA

K

J

A

D

RECOMMENDED OPERATING CONDITIONS

Condition Symbol Min Max Unit

Cathode to Anode Voltage V

Cathode Current I

KA

K

V

ref

36 V

1.0 100 mA

THERMAL CHARACTERISTICS

Characteristic Symbol

Thermal Resistance, Junction-to-Ambient

Thermal Resistance, Junction-to-Case

D, LP Suffix

Package

R

q

JA

R

q

JC

178 114 240 °C/W

83 41 - °C/W

P Suffix Package

DM Suffix

Package

Unit

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2

TL431, A, B Series, NCV431A, B

ELECTRICAL CHARACTERISTICS (T

= 25°C, unless otherwise noted.)

A

Characteristic

Reference Input Voltage (Figure 1)

V

= V

= 25°C

T

A

TA = T

, IK = 10 mA

ref

to T

low

high

(Note 1)

KA

Reference Input Voltage Deviation Over

Temperature Range (Figure 1, Notes 1, 2)

VKA= V

IK = 10 mA

ref,

Ratio of Change in Reference Input Voltage to Change in Cathode to Anode Voltage

I

= 10 mA (Figure 2),

K

= 10 V to V

DV

KA

DVKA = 36 V to 10 V

ref

Reference Input Current (Figure 2)

I

= 10 mA, R1 = 10 k, R2 = ∞

K

TA = 25°C TA = T

low

to T

high

(Note 1)

Reference Input Current Deviation Over

Temperature Range (Figure 2, Note 1, 4)

I

= 10 mA, R1 = 10 k, R2 = ∞

K

Minimum Cathode Current For Regulation

V

= V

KA

(Figure 1)

ref

Off-State Cathode Current (Figure 3)

V

= 36 V, V

KA

ref

= 0 V

Dynamic Impedance (Figure 1, Note 3)

= V

, DIK = 1.0 mA to 100 mA

ref

f ≤ 1.0 kHz

= -40 °C for TL431AIP TL431AILP, TL431IP, TL431ILP, TL431BID, TL431BIP, TL431BILP, TL431AIDM, TL431IDM, TL431BIDM; =0°C for TL431ACP, TL431ACLP, TL431CP, TL431CLP, TL431CD, TL431ACD, TL431BCD, TL431BCP, TL431BCLP, TL431CDM,

1. T

V

low

KA

TL431ACDM, TL431BCDM

= +85°C for TL431AIP, TL431AILP, TL431IP, TL431ILP, TL431BID, TL431BIP, TL431BILP, TL431IDM, TL431AIDM, TL431BIDM

T

high

= +70°C for TL431ACP, TL431ACLP, TL431CP, TL431ACD, TL431BCD, TL431BCP, TL431BCLP, TL431CDM, TL431ACDM,

TL431BCDM

2. The deviation parameter DV ambient temperature range that applies.

is defined as the difference between the maximum and minimum values obtained over the full operating

ref

max

V

ref

V

min

ref

TL431I TL431C

Symbol

V

ref

DV

ref

DV



DV

I

ref

DI

ref

I

min

I

off

Min Typ Max Min Typ Max

2.44

2.41

2.495-2.55

2.58

2.44

2.423

- 7.0 30 - 3.0 17 mV

ref

KA

-

-1.4

-

-1.0

-

1.8

-

-2.7

-2.0

4.0

-

6.5

-

- 0.8 2.5 - 0.4 1.2

- 0.5 1.0 - 0.5 1.0 mA

- 20 1000 - 20 1000 nA

2.495-2.55

-1.4

-1.0

1.8

-

|ZKA| - 0.22 0.5 - 0.22 0.5

= V

ref

min

ref

= T2 - T

A

max

ref

1

DV

-V DT

Unit

V

2.567

mV/V

-2.7

-2.0

mA

4.0

5.2

mA

W

T1

Ambient Temperature

The average temperature coefficient of the reference input voltage, aV

aV

can be positive or negative depending on whether V

ref

Example : DV

+ 8.0mVandslopeispositive,

ref

V

@25_C + 2.495V,DTA+ 70_C

ref

3. The dynamic impedance ZKA is defined as:

ref

|ZKA| +

Min or V

is defined as:

ref

Max occurs at the lower ambient temperature. (Refer to Figure 6.)

ref

0.008x10

aV

+

ref

DV

KA

. When the device is programmed with two external resistors, R1 and R2,

DI

K

(refer to Figure 2) the total dynamic impedance of the circuit is defined as:

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70(2.495)

3

T2

ǒ

ppm

V

6

+ 45.8ppmń_C

|ZKAȀ| [ |ZKA|ǒ1 )

ref

_C

+

V

DV

@25_C

ref

R1



R2

Ǔ

ref

DT

6

X10

Ǔ

A

 +

DV

DTA(V

x10

ref

@25_C)

ref

6

TL431, A, B Series, NCV431A, B

ELECTRICAL CHARACTERISTICS (T

Characteristic

Reference Input Voltage (Figure 1)

V

= V

KA

Reference Input Voltage Deviation Over

Temperature Range (Figure 1, Notes 4, 5)

Ratio of Change in Reference Input Voltage to Change in Cathode to Anode Voltage

I

K

Reference Input Current (Figure 2)

IK = 10 mA, R1 = 10 k, R2 = ∞

Reference Input Current Deviation Over

Temperature Range (Figure 2, Note 4)

Minimum Cathode Current For Regulation

VKA = V

Off-State Cathode Current (Figure 3)

V

KA

Dynamic Impedance (Figure 1, Note 6)

V

KA

4. T

low

T

high

5. The deviation parameter DV ambient temperature range that applies.

, IK = 10 mA

ref

TA = 25°C TA = T

V

KA

= V

to T

low

IK = 10 mA

ref,

high

= 10 mA (Figure 2),

= 10 V to V

DV

KA

DVKA = 36 V to 10V

ref

TA = 25°C TA = T

low

to T

high

(Note 4)

IK = 10 mA, R1 = 10 k, R2 = ∞

(Figure 1)

ref

= 36 V, V

= V

f ≤ 1.0 kHz

= 0 V

ref

, DIK = 1.0 mA to 100 mA

ref

= -40 °C for TL431AIP TL431AILP, TL431IP, TL431ILP, TL431BID, TL431BIP, TL431BILP, TL431BV, TL431AIDM, TL431IDM,

TL431BIDM, NCV431AIDMR2, NCV431AIDR2

=0°C for TL431ACP, TL431ACLP, TL431CP, TL431CLP, TL431CD, TL431ACD, TL431BCD, TL431BCP, TL431BCLP, TL431CDM,

TL431ACDM, TL431BCDM

= +85°C for TL431AIP, TL431AILP, TL431IP, TL431ILP, TL431BID, TL431BIP, TL431BILP, TL431IDM, TL431AIDM, TL431BIDM = +70°C for TL431ACP, TL431ACLP, TL431CP, TL431ACD, TL431BCD, TL431BCP, TL431BCLP, TL431CDM, TL431ACDM,

TL431BCDM

= +125°C TL431BV, NCV431AIDMR2, NCV431AIDR2, NCV431BVDMR2G

is defined as the difference between the maximum and minimum values obtained over the full operating

ref

= 25°C, unless otherwise noted.)

A

TL431BI / TL431BV

TL431AI / NCV431AI TL431AC

Symbol

V

DV

I

DI

I

Min Typ Max Min Typ Max Min Typ Max

ref

2.47

2.495-2.52

2.44

- 7.0 30 - 3.0 17 - 3.0 17 mV

ref

2.55

2.47

2.453

2.495-2.52

2.537

2.483

2.475

ref

KA

ref

min

off

---1.4

-

ref

- 0.8 2.5 - 0.4 1.2 - 0.8 2.5

- 0.5 1.0 - 0.5 1.0 - 0.5 1.0 mA

- 20 1000 - 20 1000 - 0.23 500 nA

-2.7

-1.0

-2.0--

1.8-4.0

6.5--

-1.4

-2.7

-1.0

-2.0

1.8-4.0

5.2

-

|ZKA| - 0.22 0.5 - 0.22 0.5 - 0.14 0.3

max

V

ref

V

min

ref

DV

-V DT

= V

ref

min

ref

= T2 - T

A

max

ref

1

NCV431BV

2.495

-1.4

-1.0

1.1-2.0

Unit

V

2.507

2.515

mV/V

-2.7

-2.0

mA

4.0

mA

W

T1

Ambient Temperature

The average temperature coefficient of the reference input voltage, aV

aV

can be positive or negative depending on whether V

ref

Example : DV

+ 8.0mVandslopeispositive,

ref

V

@25_C + 2.495V,DTA+ 70_C

ref

6. The dynamic impedance ZKA is defined as

ref

|ZKA| +

Min or V

ref

DV

KA

When the device is programmed with two external resistors, R1 and R2, (refer

DI

K

to Figure 2) the total dynamic impedance of the circuit is defined as:

7. NCV431AIDMR2, NCV431AIDR2, NCV431BVDMR2G T and other applications requiring site and change control.

low

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T2

is defined as:

ref

Max occurs at the lower ambient temperature. (Refer to Figure 6.)

0.008x10

aV

+

ref

70(2.495)

|ZKAȀ| [ |ZKA|ǒ1 )

= -40°C, T

= +125°C. Guaranteed by design. NCV prefix is for automotive

high

ppm

V

ref

_C

6

+ 45.8ppmń_C

DV

ref

ǒ

V

@25_C

ref

+

R1 R2

DT

A

Ǔ



Ǔ

X10

6

 +

4

DV

DTA(V

x10

ref

@25_C)

ref

6

TL431, A, B Series, NCV431A, B

Input

V

ref

V

KA

I

K

Figure 1. Test Circuit for VKA = V

150

VKA = V

ref

100

TA = 25°C

Input V

I

K

KA

50

0

, CATHODE CURRENT (mA)

-50

K

I

-100

-2.0 -1.0 0

, CATHODE VOLTAGE (V)

V

KA

Figure 4. Cathode Current versus

Cathode Voltage

Input

R1

R2

V

ref

Figure 2. Test Circuit for V

1.0 2.0 3.0

V

KA

I

K

ref

ǒ1 )

KA

> V

R1 R2

Ǔ) I

ref

SR1

ref

Figure 3. Test Circuit for I

VKA+ V

Input V

I

off

KA

off

800

V

= V

KA

ref

600

Input

TA = 25°C

V

KA

I

K

I

Min

400

200

, CATHODE CURRENT ( A)μ

0

K

I

-200

-1.0

0

V

, CATHODE VOLTAGE (V)

KA

1.0 2.0 3.0

Figure 5. Cathode Current versus

Cathode Voltage

2600

2580

2560

2540

2520

2500

2480 2460

2440

2420

ref

V , REFERENCE INPUT VOLTAGE (mV)

2400

-55

V

Input

V

ref

KA

I

K

VKA = V

ref

IK = 10 mA

050

25-25

T

, AMBIENT TEMPERATURE (°C)

A

V

ref

Max = 2550 mV

V

Typ = 2495 mV

ref

V

Min = 2440 mV

ref

75 100 125

Figure 6. Reference Input Voltage versus

Ambient Temperature

3.0

2.5

2.0

1.5 IK = 10 mA

Input

1.0

0.5

, REFERENCE INPUT CURRENT ( A)μ

ref

I

0

10k

I

ref

V

KA

I

K

250-25

T

, AMBIENT TEMPERATURE (°C)

A

125

10050 75-55

Figure 7. Reference Input Current versus

Ambient Temperature

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5

TL431, A, B Series, NCV431A, B

0

-8.0

-16

-24

, REFERENCE INPUT VOLTAGE (mV)Δ

ref

V

-32

100

Ω|, DYNAMIC IMPEDANCE ( )

10

Input V

R1

R2

V

ref

KA

I

K

20

VKA, CATHODE VOLTAGE (V)

Figure 8. Change in Reference Input

Voltage versus Cathode Voltage

1.0 k

50

Output

I

K

-

+

GND

TA = 25°C D I

K

IK = 10 mA T

= 25°C

A

30100

= 1.0 mA to 100 mA

1.0 k

100

10

VKA = 36 V

= 0 V

V

1.0 Input

ref

V

KA

I

off

0.1

, OFF-STATE CATHODE CURRENT (nA)

off

I

0.01

40

-55

T

, AMBIENT TEMPERATURE (5C)

A

75-25 0 25 50 100 125

Figure 9. Off-State Cathode Current

versus Ambient Temperature

0.320 V

= V

KA

Ω|, DYNAMIC IMPEDANCE ( )

0.300

0.280

0.260

ref

D IK = 1.0 mA to 100 mA f ≤ 1.0 kHz

1.0k 50

Output

I

K

+

GND

1.0

KA

|Z

0.1

60

50

40

30

20

IK = 10 mA

10

, OPEN LOOP VOLTAGE GAIN (dB)

A

TA = 25°C

0

VOL

-10

1.0 k 10 k

100 k 10 M1.0 M1.0 k 10 k

f, FREQUENCY (MHz)

Figure 10. Dynamic Impedance

versus Frequency

I

K

15k

9.0 mF

8.25k

100 k

f, FREQUENCY (MHz)

230

Output

GND

0.240

KA

0.220

|Z

0.200

-55

T

, AMBIENT TEMPERATURE (°C)

A

75-25 0 25 50 100 125

Figure 11. Dynamic Impedance

versus Ambient Temperature

80

60

√

VKA = V

40

20

NOISE VOLTAGE (nV/ Hz)

0

10 M1.0 M

10 10 k1.0 k100

f, FREQUENCY (Hz)

I

= 10 mA

K

T

= 25°C

A

ref

OutputInput

I

K

100 k

Figure 12. Open-Loop Voltage Gain

versus Frequency

Figure 13. Spectral Noise Density

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6

TL431, A, B Series, NCV431A, B

TA = 25°C

3.0

2.0

1.0

0

VOLTAGE SWING (V)

5.0

0

0 8.04.0 20

Output

Input

t, TIME (ms)

Input

Monitor

Pulse

Generator

f = 100 kHz

12

Figure 14. Pulse Response Figure 15. Stability Boundary Conditions

150

I

K

V+

C

140

Unstable

, CATHODE CURRENT (mA)

K

I

120

100

80

60

40

20

0

1.0 nF

Output

220

50

GND

16

L

Programmed

Area

A B C D

(V)

V

KA

V

ref

5.0 10 15

Stable Stable

A

10 nF 100 nF

, LOAD CAPACITANCE

C

L

150

V+

C

D

B

I

K

10 k

TA = 25°C

B

A

100 mF1.0 mF10 mF

C

L

Figure 16. Test Circuit For Curve A

of Stability Boundary Conditions

Figure 17. Test Circuit For Curves B, C, And D

of Stability Boundary Conditions

TYPICAL APPLICATIONS

V+

R1

R2

R1

ǒ

V

+

out

1 )

R2

Ǔ

V

V

out

ref

Figure 18. Shunt Regulator Figure 19. High Current Shunt Regulator

V+ V

R1

R2

R1

ǒ

Ǔ

1 )

V

+

out

R2

V

out

ref

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7

TL431, A, B Series, NCV431A, B

MC7805

V+ V

In

V

Common

V

out

out(min)

+

Out

ǒ

1 )

+ V

R1 R2

ref

Ǔ

V

ref

) 5.0V

Figure 20. Output Control for a

Three-T erminal Fixed Regulator

R

V+

I

+

out

CL

V

ref

R

CL

R2

R1

V+

out

R1

ǒ

Ǔ

1 )

out

+ V

R2

) V

ref

V

ref

be

V

out

V

in(min)

+

V

out(min)

+ V

R1

R2

V

out

Figure 21. Series Pass Regulator

I

out

V+

I

sink

V

I

Sink

R

S

ref

+

R

S

Figure 22. Constant Current Source Figure 23. Constant Current Sink

V+

V

out(trip)

+

ǒ

1 )

R1 R2

V

out

R1

R2

Ǔ

V

ref

V+

V

out(trip)

+

ǒ

1 )

R1 R2

R1

R2

Ǔ

V

ref

Figure 24. TRIAC Crowbar Figure 25. SRC Crowbar

V

out

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8

TL431, A, B Series, NCV431A, B

5.0 k 1%

10 kW

1.0 kW V

V+

l

L.E.D. indicator is `on' when V+ is between the upper and lower limits.

LowerLimit +

UpperLimit +

R1 R3

R2 R4

R1

ǒ

1 )

R2 R3

ǒ

1 )

R4

Figure 26. Voltage Monitor Figure 27. Single-Supply Comparator with

25 V

V

W

D

 Range

out

V

50 k

1%

1N5305

5.0 M

500 k

V

R

1%

X

100 kW

V

Range

1%

1.0 MW

Rx+ V

Ǔ

V

Ǔ

V

2.0 mA

-

LM11

+

ref

Calibrate

25 V

-5.0 V

10 k

V

out

V

in

Vth = V

V+

V

out

ref

V

< V

> V

V

in

out

V+

ref

≈ 2.0 V

ref

Temperature-Compensated Threshold

38 V

T

= 330 to 8.0 W

l

T

I

8.0 W

V

out

*Thermalloy

*THM 6024 *Heatsink on *LP Package

*

330

+

470 mF

360 k

1.0 mF

0.05 mF

Tone

56 k 10 k 25 k

Volume

47 k

Figure 28. Linear Ohmmeter Figure 29. Simple 400 mW Phono Amplifier

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9

TL431, A, B Series, NCV431A, B

= 10 V to 20 V

V

in

150 mH @ 2.0 A

TIP115

1.0 k

4.7 k

+

2200 mF

MPSA20

4.7 k

0.1 mF

102.2 k

4.7 k

1N5823

0.01mF

100 k

51 k

Figure 30. High Efficiency Step-Down Switching Converter

Test Conditions Results

Line Regulation Vin = 10 V to 20 V, Io = 1.0 A 53 mV (1.1%)

Load Regulation Vin = 15 V, Io = 0 A to 1.0 A 25 mV (0.5%)

Output Ripple Vin = 10 V, Io = 1.0 A 50 mVpp P.A.R.D.

Output Ripple Vin = 20 V, Io = 1.0 A 100 mVpp P.A.R.D.

Efficiency Vin = 15 V, Io = 1.0 A 82%

470 mF

= 5.0 V

V

out

I

= 1.0 A

out

+

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10

TL431, A, B Series, NCV431A, B

APPLICATIONS INFORMATION

The TL431 is a programmable precision reference which is used in a variety of ways. It serves as a reference voltage in circuits where a non-standard reference voltage is needed. Other uses include feedback control for driving an optocoupler in power supplies, voltage monitor, constant current source, constant current sink and series pass regulator. In each of these applications, it is critical to maintain stability of the device at various operating currents and load capacitances. In some cases the circuit designer can estimate the stabilization capacitance from the stability boundary conditions curve provided in Figure 15. However, these typical curves only provide stability information at specific cathode voltages and at a specific load condition. Additional information is needed to determine the capacitance needed to optimize phase margin or allow for process variation.

A simplified model of the TL431 is shown in Figure 31. When tested for stability boundaries, the load resistance is 150 W. The model reference input consists of an input transistor and a dc emitter resistance connected to the device anode. A dependent current source, Gm, develops a current whose amplitude is determined by the difference between the 1.78 V internal reference voltage source and the input transistor emitter voltage. A portion of Gm flows through compensation capacitance, C

. The voltage across C

P2

drives the output dependent current source, Go, which is connected across the device cathode and anode.

Model component values are:

V

= 1.78 V

ref

Gm = 0.3 + 2.7 exp (-I

where IC is the device cathode current and Gm is in mhos

/26 mA)

C

Go = 1.25 (Vcp2) mmhos.

Resistor and capacitor typical values are shown on the model. Process tolerances are ±20% for resistors, ±10% for capacitors, and ±40% for transconductances.

An examination of the device model reveals the location of circuit poles and zeroes:

P1 +

1

2pRGMC

+

2p * 1.0M * 20pF

P1

1

+ 7.96kHz

P2 +

Z1 +

1

2pRP2C

1

2pRZ1C

+

2p * 10M * 0.265pF

P2

+

2p * 15.9k * 20pF

P1

1

+ 60kHz

+ 500kHz

In addition, there is an external circuit pole defined by the

load:

PL+

1

2pRLC

L

Also, the transfer dc voltage gain of the TL431 is:

G + GMRGMGoR

L

Example 1:

IC+10mA, RL+ 230W,CL+ 0.Definethetransfergain.

The DC gain is:

G + GMRGMGoRL+

(2.138)(1.0M)(1.25m)(230) + 615 + 56dB

Loopgain + G

8.25k

8.25k ) 15k

+ 218 + 47dB

The resulting transfer function Bode plot is shown in Figure 32. The asymptotic plot may be expressed as the following equation:

Av + 615

ǒ

1 )

ǒ

1 )

8.0kHz

jf

500kHz

Ǔǒ

1 )

Ǔ

jf

60kHz

Ǔ

The Bode plot shows a unity gain crossover frequency of approximately 600 kHz. The phase margin, calculated from the equation, would be 55.9 degrees. This model matches the Open-Loop Bode Plot of Figure 12. The total loop would have a unity gain frequency of about 300 kHz with a phase margin of about 44 degrees.

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11

Input

8.25 k

9.0 mF

15 k

TL431, A, B Series, NCV431A, B

V

CC

R

L

C

L

3

Cathode

R

P2

Ref

1

500 k

V

ref

1.78 V

G

+

R

ref

-

16

M

R

GM

1.0 M

Anode 2

20 pF

10 M

C

P1

R

Z1

15.9 k

Figure 31. Simplified TL431 Device Model

Go

1.0 mmho

C

P2

0.265 pF

TL431 OPEN-LOOP VOLTAGE GAIN VERSUS FREQUENCY

60

50

40

30

20

10

0

-10

Av, OPEN-LOOP VOLTAGE GAIN (dB)

-20 10

2

1

10

3

10

f, FREQUENCY (Hz)

4

10

5

10

6

10

Figure 32. Example 1 Circuit Open Loop Gain Plot

Example 2.

= 7.5 mA, RL = 2.2 kW, CL = 0.01 mF. Cathode tied to

I

C

reference input pin. An examination of the data sheet stability boundary curve (Figure 15) shows that this value of load capacitance and cathode current is on the boundary. Define the transfer gain.

The DC gain is:

G + GMRGMGoRL+

(2.323)(1.0M)(1.25m)(2200) + 6389 + 76dB

The resulting open loop Bode plot is shown in Figure 33. The asymptotic plot may be expressed as the following equation:

1 )

jf

500kHz

jf

60kHz

Ǔ

Ǔǒ

1 )

jf

7.2kHz

Ǔ

Av + 615

ǒ

1 )

jf

8.0kHz

Ǔǒ

ǒ

1 )

Note that the transfer function now has an extra pole

formed by the load capacitance and load resistance.

Note that the crossover frequency in this case is about 250 kHz, having a phase margin of about -46 degrees. Therefore, instability of this circuit is likely.

80

60

40

7

20

Av, OPEN-LOOP GAIN (dB)

0

-20

Figure 33. Example 2 Circuit Open Loop Gain Plot

TL431 OPEN-LOOP BODE PLOT WITH LOAD CAP

1

10

2

10

3

10

f, FREQUENCY (Hz)

10

4

With three poles, this system is unstable. The only hope for stabilizing this circuit is to add a zero. However, that can only be done by adding a series resistance to the output capacitance, which will reduce its effectiveness as a noise filter. Therefore, practically, in reference voltage applications, the best solution appears to be to use a smaller value of capacitance in low noise applications or a very large value to provide noise filtering and a dominant pole rolloff of the system.

5

10

6

10

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12

TL431, A, B Series, NCV431A, B

ORDERING INFORMATION

Device Operating Temperature Range Package Code Shipping Information

TL431ACD

TL431ACDG

TL431BCD

TL431BCDG

TL431CD

TL431CDG

TL431ACDR2

TL431ACDR2G

TL431BCDR2

TL431BCDR2G

TL431CDR2

TL431CDR2G

TL431ACDMR2

TL431ACDMR2G

TL431BCDMR2

TL431BCDMR2G

TL431CDMR2

TL431CDMR2G

TL431ACP

TL431ACPG

TL431BCP

TL431BCPG

TL431CP

TL431CPG

TL431ACLP

TL431ACLPG

TL431BCLP

TL431BCLPG

TL431CLP

TL431CLPG

TL431ACLPRA

TL431ACLPRAG

†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging

Specifications Brochure, BRD8011/D.

0°C to 70°C

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

SOIC-8 2.2%

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

Micro8

(Pb-Free)

Micro8

(Pb-Free)

Micro8

(Pb-Free)

PDIP-8

(Pb-Free)

PDIP-8 0.4%

PDIP-8

(Pb-Free)

PDIP-8

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

98 Units / Rail

2500 Units / Tape & Reel

4000 Units / Tape & Reel

50 Units / Rail

2000 Units / Bag

2000 Units / Tape & Reel 1.0%

†

Tolerance

1.0%

0.4%

2.2%

1.0%

0.4%

2.2%

1.0%

0.4%

2.2%

1.0%

0.4%

2.2%

1.0%

0.4%

2.2%

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13

TL431, A, B Series, NCV431A, B

ORDERING INFORMATION

Device Operating Temperature Range Package Code Shipping Information

TL431BCLPRA

TL431BCLPRAG

TL431CLPRA

TL431CLPRAG

TL431ACLPRE

TL431ACLPREG

TL431BCLPRE

TL431BCLPREG

TL431ACLPRP

TL431ACLPRPG

TL431BCLPRM

TL431BCLPRMG

TL431CLPRP

TL431CLPRPG

TL431AID

TL431AIDG

TL431BID

TL431BIDG

TL431ID

TL431IDG

TL431AIDR2

TL431AIDR2G

TL431BIDR2

TL431BIDR2G

TL431IDR2

TL431IDR2G

TL431AIDMR2

TL431AIDMR2G

TL431BIDMR2

TL431BIDMR2G

TL431IDMR2

TL431IDMR2G

†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging

Specifications Brochure, BRD8011/D.

0°C to 70°C

-40 °C to 85°C

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226) 0.4%

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

Micro8

(Pb-Free)

Micro8

(Pb-Free)

Micro8

(Pb-Free)

2000 Units / Tape & Reel

2000 / Tape & Ammo Box 1.0%

2000 Units / Fan-Fold

98 Units / Rail

2500 Units / Tape & Reel

4000 Units / Tape & Reel

†

Tolerance

0.4%

2.2%

1.0%

0.4%

2.2%

1.0%

0.4%

2.2%

1.0%

0.4%

2.2%

1.0%

0.4%

2.2%

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14

TL431, A, B Series, NCV431A, B

ORDERING INFORMATION

Device Operating Temperature Range Package Code Shipping Information

TL431AIP

TL431AIPG

TL431BIP

TL431BIPG

TL431IP

TL431IPG

TL431AILP

TL431AILPG

TL431BILP

TL431BILPG

TL431ILP

TL431ILPG

TL431AILPRA

TL431AILPRAG

TL431BILPRA

TL431BILPRAG

TL431ILPRA

TL431ILPRAG

TL431AILPRM

TL431AILPRMG

TL431AILPRP

TL431AILPRPG

TL431ILPRP

TL431ILPRPG

TL431BVD

TL431BVDG

TL431BVDR2

TL431BVDR2G

TL431BVDMR2

TL431BVDMR2G

TL431BVLP

TL431BVLPG

TL431BVLPRAG

†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging

Specifications Brochure, BRD8011/D.

-40 °C to 85°C

-40 °C to 125°C

PDIP-8

(Pb-Free)

PDIP-8 0.4%

PDIP-8

(Pb-Free)

PDIP-8 2.2%

PDIP-8

(Pb-Free)

TO-92 (TO-226)

TO-92 (TO-226) 1.0%

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226) 1.0%

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226) 2.2%

TO-92 (TO-226)

(Pb-Free)

SOIC-8

(Pb-Free)

SOIC-8

(Pb-Free)

Micro8

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

TO-92 (TO-226)

(Pb-Free)

50 Units / Rail

2000 Units / Bag

2000 Units / Tape & Reel

2000 / Tape & Ammo Box

98 Units / Rail

2500 Units / Tape & Reel

4000 Units / Tape & Reel

2000 Units / Bag

2000 Units / Tape & Reel 0.4%

†

Tolerance

1.0%

0.4%

2.2%

1.0%

0.4%

2.2%

1.0%

0.4%

2.2%

1.0%

2.2%

0.4%

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15

TL431, A, B Series, NCV431A, B

ORDERING INFORMATION

Device Operating Temperature Range Package Code Shipping Information

TL431BVP

TL431BVPG

NCV431AIDMR2

NCV431AIDMR2G

-40 °C to 125°C

NCV431AIDR2

NCV431AIDR2G

NCV431BVDMR2G

†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging

Specifications Brochure, BRD8011/D.

PDIP-8

(Pb-Free)

Micro8

(Pb-Free)

SOIC-8

(Pb-Free)

Micro8

(Pb-Free)

50 Units / Rail

4000 Units / Tape & Reel

2500 Units / Tape & Reel

4000 Units / Tape & Reel 0.4%

MARKING DIAGRAMS

†

Tolerance

0.4%

1%

SOIC-8

D SUFFIX

CASE 751

8

431xx ALYW

1

Micro8

CASE 846A

8

xxx

G

AYW G

G

1

xxxx = Specific Device Code A = Assembly Location Y, YY = Year WW, W = Work Week G or G = Pb-Free Package

(Note: Microdot may be in either location)

PDIP-8

CASE 626

8

TL431xx

AWL

YYWWG

1

TO-92 (TO-226)

CASE 29

TL431

xxxx

YWWG

G

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16

TL431, A, B Series, NCV431A, B

PACKAGE DIMENSIONS

TO-92 (TO-226)

CASE 29-11

ISSUE AM

1

2

3

STRAIGHT LEAD

BULK PACK

SEATING PLANE

R

T

SEATING PLANE

G

R

P

XX

1

2

3

BENT LEAD

TAPE & REEL

AMMO PACK

A

G

H

V

1

N

A

V

1

B

STRAIGHT LEAD

BULK PACK

P

L

K

D

J

C

SECTION X-X

N

B

BENT LEAD

TAPE & REEL

AMMO PACK

K

D

J

C

SECTION X-X

NOTES:

1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982.

2. CONTROLLING DIMENSION: INCH.

3. CONTOUR OF PACKAGE BEYOND DIMENSION R IS UNCONTROLLED.

4. LEAD DIMENSION IS UNCONTROLLED IN P AND BEYOND DIMENSION K MINIMUM.

DIM MIN MAX MIN MAX

A 0.175 0.205 4.45 5.20 B 0.170 0.210 4.32 5.33 C 0.125 0.165 3.18 4.19 D 0.016 0.021 0.407 0.533 G 0.045 0.055 1.15 1.39 H 0.095 0.105 2.42 2.66

J 0.015 0.020 0.39 0.50

K 0.500 --- 12.70 ---

L 0.250 --- 6.35 ---

N 0.080 0.105 2.04 2.66

P --- 0.100 --- 2.54

R 0.115 --- 2.93 ---

V 0.135 --- 3.43 ---

NOTES:

1. DIMENSIONING AND TOLERANCING PER ASME Y14.5M, 1994.

2. CONTROLLING DIMENSION: MILLIMETERS.

3. CONTOUR OF PACKAGE BEYOND DIMENSION R IS UNCONTROLLED.

4. LEAD DIMENSION IS UNCONTROLLED IN P AND BEYOND DIMENSION K MINIMUM.

MILLIMETERS

DIM MIN MAX

A 4.45 5.20 B 4.32 5.33 C 3.18 4.19 D 0.40 0.54 G 2.40 2.80 J 0.39 0.50 K 12.70 --- N 2.04 2.66 P 1.50 4.00 R 2.93 --- V 3.43 ---

MILLIMETERSINCHES

N

http://onsemi.com

17

NOTE 2

-T-

SEATING PLANE

H

58

-B-

14

F

-A-

C

N

D

G

0.13 (0.005) B

TL431, A, B Series, NCV431A, B

PDIP-8

P SUFFIX

PLASTIC PACKAGE

CASE 626-05

ISSUE L

L

J

K

M

A

T

M

NOTES:

1. DIMENSION L TO CENTER OF LEAD WHEN FORMED PARALLEL.

2. PACKAGE CONTOUR OPTIONAL (ROUND OR SQUARE CORNERS).

3. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982.

DIM MIN MAX MIN MAX

A 9.40 10.16 0.370 0.400 B 6.10 6.60 0.240 0.260 C 3.94 4.45 0.155 0.175 D 0.38 0.51 0.015 0.020 F 1.02 1.78 0.040 0.070 G 2.54 BSC 0.100 BSC H 0.76 1.27 0.030 0.050 J 0.20 0.30 0.008 0.012 K 2.92 3.43 0.115 0.135 L 7.62 BSC 0.300 BSC M --- 10 --- 10 N 0.76 1.01 0.030 0.040

INCHESMILLIMETERS

__

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18

-T-

0.038 (0.0015)

PIN 1 ID

SEATING PLANE

TL431, A, B Series, NCV431A, B

PACKAGE DIMENSIONS

Micro8

DM SUFFIX

PLASTIC PACKAGE

CASE 846A-02

ISSUE G

DD

H

E

e

E

8 PL

b

0.08 (0.003) A

M

T

S

B

S

A

NOTES:

1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982.

2. CONTROLLING DIMENSION: MILLIMETER.

3. DIMENSION A DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED

0.15 (0.006) PER SIDE.

4. DIMENSION B DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSION. INTERLEAD FLASH OR PROTRUSION SHALL NOT EXCEED 0.25 (0.010) PER SIDE.

5. 846A-01 OBSOLETE, NEW STANDARD 846A-02.

DIMAMIN NOM MAX MIN

A1 0.05 0.08 0.15 0.002

b 0.25 0.33 0.40 0.010 c 0.13 0.18 0.23 0.005 D 2.90 3.00 3.10 0.114 E 2.90 3.00 3.10 0.114 e 0.65 BSC L 0.40 0.55 0.70 0.016

H

MILLIMETERS

-- -- 1.10 --

4.75 4.90 5.05 0.187 0.193 0.199

E

INCHES

NOM MAX

-- 0.043

0.003 0.006

0.013 0.016

0.007 0.009

0.118 0.122

0.026 BSC

0.021 0.028

A1

c

L

SOLDERING FOOTPRINT*

1.04

8X

0.041

3.20

0.126

0.65

6X

0.0256

*For additional information on our Pb-Free strategy and soldering

details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D.

0.38

0.015

8X

4.24

0.167

SCALE 8:1

5.28

0.208

ǒ

inches

mm

Ǔ

http://onsemi.com

19

-Z-

-Y-

TL431, A, B Series, NCV431A, B

SOIC-8

D SUFFIX

PLASTIC PACKAGE

CASE 751-07

ISSUE AH

-XA

58

B

1

S

0.25 (0.010)

4

M

Y

K

G

C

SEATING PLANE

0.10 (0.004)

H

D

0.25 (0.010) Z

M

SXS

Y

N

X 45

_

M

J

NOTES:

1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982.

2. CONTROLLING DIMENSION: MILLIMETER.

3. DIMENSION A AND B DO NOT INCLUDE MOLD PROTRUSION.

4. MAXIMUM MOLD PROTRUSION 0.15 (0.006) PER SIDE.

5. DIMENSION D DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE 0.127 (0.005) TOTAL IN EXCESS OF THE D DIMENSION AT MAXIMUM MATERIAL CONDITION.

6. 751-01 THRU 751-06 ARE OBSOLETE. NEW STANDARD IS 751-07.

MILLIMETERS

DIMAMIN MAX MIN MAX

4.80 5.00 0.189 0.197

B 3.80 4.00 0.150 0.157 C 1.35 1.75 0.053 0.069 D 0.33 0.51 0.013 0.020 G 1.27 BSC 0.050 BSC H 0.10 0.25 0.004 0.010

J 0.19 0.25 0.007 0.010 K 0.40 1.27 0.016 0.050 M 0 8 0 8

____

N 0.25 0.50 0.010 0.020 S 5.80 6.20 0.228 0.244

INCHES

SOLDERING FOOTPRINT*

1.52

0.060

7.0

0.275

0.6

0.024

*For additional information on our Pb-Free strategy and soldering

details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D.

Micro8 is a trademark of International Rectifier.

ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer's technical experts. SCILLC does not convey any license under its patent rights nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.

4.0

0.155

1.270

0.050

SCALE 6:1

ǒ

inches

mm

Ǔ

PUBLICATION ORDERING INFORMATION

LITERATURE FULFILLMENT:

Literature Distribution Center for ON Semiconductor P.O. Box 5163, Denver, Colorado 80217 USA Phone: 303-675-2175 or 800-344-3860 Toll Free USA/Canada Fax: 303-675-2176 or 800-344-3867 Toll Free USA/Canada Email: [email protected]

N. American Technical Support: 800-282-9855 Toll Free USA/Canada

Europe, Middle East and Africa Technical Support:

Phone: 421 33 790 2910

Japan Customer Focus Center

Phone: 81-3-5773-3850

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20

ON Semiconductor Website: www.onsemi.com

Order Literature: http://www.onsemi.com/orderlit

For additional information, please contact your local Sales Representative

TL431/D