2

 2003 Semtech Corp.

www.semtech.com

POWER MANAGEMENT

SC4431

Shunt Regulator With

Open Collector Output

T

,

d

e

i

fi

c

e

p

s

s

s

e

l

n

U

A

V

,

C

°

5

2

=

C

C

I

,

V

2

=

T

U

O

n

i

s

e

u

l

a

V

.

A

m

2

=

d

l

o

b

.

e

g

n

a

r

e

r

u

t

a

r

e

p

m

e

t

g

n

i

t

a

r

e

p

o

ll

u

f

r

e

v

o

y

l

p

p

a

r

e

t

e

m

a

r

a

Pl

o

b

m

y

Ss

n

o

i

t

i

d

n

o

C

t

s

e

TN

I

MP

Y

TX

A

Ms

t

i

n

U

C

C

V

e

g

a

tl

o

V

y

l

p

p

u

S

t

u

p

n

IV

C

C

5

.

15

1

V

t

n

e

r

r

u

C

y

l

p

p

u

S

t

u

p

n

II

C

C

V

F

E

R

V

=

T

U

O

0

1

1

0

0

2

A

µ

t

n

e

r

r

u

C

y

l

p

p

u

S

t

u

p

n

I

e

t

a

t

S

f

f

OI

)

F

F

O

(

C

C

V

F

E

R

V

,

V

7

8

1

.

1

=

T

U

O

V

2

=5

60

0

1A

µ

0

5

1

F

E

R

e

g

a

tl

o

V

e

c

n

e

r

e

f

e

RV

F

E

R

V

,

5

.

-

1

3

4

4

C

S

F

E

R

V

=

T

U

O

9

1

2

.

14

2

2

.

11

3

2

.

1V

7

0

2

.

13

4

2

.

1

V

,

1

-

1

3

4

4

C

S

F

E

R

V

=

T

U

O

2

1

2

.

14

2

2

.

16

3

2

.

1V

0

0

2

.

10

5

2

.

1

V

,

2

-

1

3

4

4

C

S

F

E

R

V

=

T

U

O

0

0

2

.

14

2

2

.

10

5

2

.

1V

7

8

1

.

11

6

2

.

1

V

n

i

e

g

n

a

h

C

F

E

R

n

i

e

g

n

a

h

c

o

t

e

u

d

c

c

V

V

d

F

E

R

V

d

/

C

C

V

C

C

V

5

1

o

t

V

5

.

1

=8

5

1V

m

0

2

V

n

i

e

g

n

a

h

C

F

E

R

t

e

u

dg

n

a

h

c

oe n

i

I

T

U

O

V

d

F

E

R

I

d

/

T

U

O

I

T

U

O

A

m

0

4

o

t

A

m

1

.

0

=8

8

2V

m

6

3

t

n

e

r

r

u

C

t

u

p

n

I

e

c

n

e

r

e

f

e

RI

F

E

R

A

m

1

.

0

≤ I

T

U

O

≤

A

m

0

13

.

05

.

0A

µ

0

.

1

T

U

O

e

g

a

tl

o

V

n

o

i

t

a

r

u

t

a

SV

)

T

A

S

(

T

U

O

I

T

U

O

I

,

A

m

5

=

C

C

A

µ

0

0

5

=0

55

7V

m

0

0

1

V

F

E

R

I

,

V

1

6

2

.

1

=

T

U

O

A

m

0

4

=5

7

20

0

3V

m

0

0

4

t

n

e

r

r

u

C

t

u

p

t

u

O

e

t

a

t

S

f

f

OI

)

F

F

O

(

T

U

O

V

F

E

R

V

,

V

7

8

1

.

1

=

T

U

O

V

2

=0

5

.

01

A

µ

0

1

r

e

t

e

m

a

r

a

P

l

o

b

m

y

Sm

u

m

i

x

a

Ms

t

i

n

U

e

g

a

tl

o

V

y

l

p

p

u

S

t

u

p

n

I

V

C

C

6

1

+

o

t

5

.

0

-V

t

n

e

r

r

u

c

n

i

p

c

c

V

I

C

C

8A

m

e

g

a

tl

o

V

t

u

p

t

u

O

V

T

U

O

C

C

V

o

t

5

.

0

-V

e

g

a

tl

o

V

e

c

n

e

r

e

f

e

R

)

1

(

V

F

E

R

4

+

o

t

5

.

0

-V

t

n

e

r

r

u

C

t

u

p

t

u

O

s

u

o

u

n

it

n

o

C

I

T

U

O

0

4A

m

t

n

e

r

r

u

C

t

u

p

n

I

e

c

n

e

r

e

f

e

R

I

F

E

R

5A

m

e

g

n

a

R

e

r

u

t

a

r

e

p

m

e

T

t

n

e

i

b

m

A

g

n

it

a

r

e

p

O

T

A

5

8

+

o

t

0

4

-C

°

e

g

n

a

R

e

r

u

t

a

r

e

p

m

e

T

n

o

it

c

n

u

J

g

n

it

a

r

e

p

O

T

J

0

5

1

+

o

t

0

4

-C

°

e

g

n

a

R

e

r

u

t

a

r

e

p

m

e

T

e

g

a

r

o

t

S

T

G

T

S

0

5

1

+

o

t

5

6

-C

°

t

n

e

i

b

m

A

o

t

n

o

it

c

n

u

J

e

c

n

a

d

e

p

m

I

l

a

m

r

e

h

T

θ

A

J

6

5

2W

/

C

°

e

s

a

C

o

t

n

o

it

c

n

u

J

e

c

n

a

d

e

p

m

I

l

a

m

r

e

h

T

θ

C

J

1

8W

/

C

°

T

t

a

n

o

it

a

p

i

s

s

i

D

r

e

w

o

P

A

C

°

5

2

=P

D

5

7

4W

m

s

d

n

o

c

e

s

0

1

)

g

n

ir

e

d

l

o

S

(

e

r

u

t

a

r

e

p

m

e

T

d

a

e

L

T

D

A

E

L

0

0

3C

°

)l

e

d

o

M

y

d

o

B

n

a

m

u

H

(

g

n

it

a

R

D

S

E

D

S

E2

V

k

Absolute Maximum Rating

Electrical Characteristics

(1) If Vref will be forced above 1.224V, a resistor must be placed in series with the Vcc to limit the Icc current

below 5mA.