© 2014 Littelfuse, Inc.

Specifications are subject to change without notice.

Revised: 05/23/14

Varistor Products

Thermally Protected Varistors > SMOV25S Series

Product Dimensions

31Max

16.5Max

2±0.3

3.5±0.2

3*0.6±0.2

0.3±0.2

1.3±0.3

1.4±0.2

0.5±0.2

4.0±1.2

13.4±0.2

LF 9

SMOV25S321MP

1148

3.5±0.2

Application Example

Thermal

disconnect

MOV

S1 ON

S3 Common

S2 OFF

P1

P2

Primary side

Secondary side

Galvanic isolation

Note: EXAMPLE ONLY - Connection to S2-S3 and S1-S3

depends on customer indication circuit and can vary.

R

LED

* LED is off when the product is normal(S1,S3 connected),

LED is on when the product disconect opens(switch change

status; S2,S3 connected as shown by dotted line ).

Thermal

disconnect

MOV

S1 ON

(Normal Close)

S3 Common

S2 OFF

(Normal open)

P1

P2

Primary side

Secondary side

Galvanic isolation

LF9

SMOVXXS321MP

1209

S2 S3 S1

P2

P1

P2

P1

S2 S3 S1

Thermal

disconnect

MOV

S1 ON

S3 Common

S2 OFF

P1

P2

Primary side

Secondary side

Galvanic isolation

Note: EXAMPLE ONLY - Connection to S2-S3 and S1-S3

depends on customer indication circuit and can vary.

R

LED

* LED is off when the product is normal(S1,S3 connected),

LED is on when the product disconect opens(switch change

status; S2,S3 connected as shown by dotted line ).

Thermal

disconnect

MOV

S1 ON

(Normal Close)

S3 Common

S2 OFF

(Normal open)

P1

P2

Primary side

Secondary side

Galvanic isolation

LF9

SMOVXXS321MP

1209

S2 S3 S1

P2

P1

P2

P1

S2 S3 S1

Lead Configuration

SMOV Switch

Voltage DC

Current (Amps)

Contact Resistance Max. Insulation Resistance Min.

Dialectric Strength

0.5mA/Minute

Switch

12V

0.1A

70mΩ

100MΩ

500VAC

Switch Specification