MDSM-4R 12-18 - LITTELFUSE

Speciﬁcations are subject to change without notice.

MDSM-4 15.3mm Surface Mount Reed Switch

Description

The MDSM-4 surface mount reed switch is a sub-miniature, normally open

switch with a 15.24mm long x 2.28mm diameter (0.600” x 0.090”) glass

envelope, capable of switching 200Vdc at 10W.

This reed switch is a surface mount version of MDCG-4. It has high insulation

resistance of 1010 ohms minimum and a contact resistance of less than

100 milliohms.

Agency Approvals

Agency Agency File Number Ampere-Turns Range

E47258

E471070 12-38 AT

Switch Type

Contact Form A (SPST-NO)

Materials Body: Glass

Leads: Tin-plated Ni-Fe wire

Surface Mount Reed Switches

Features

• Surface mount, normally

open switch

• Low, stable contact resistance

• Capable of switching 200Vdc or

0.5A at up to 10W

• Available sensitivity 12-38 AT

Benefits

• Hermetically sealed switch

contacts are not affected by and

have no effect on their external

environment

• Zero operating power required for

contact closure

• Excellent for switching micro-

controller logic level loads

Applications

• Position Sensing

• Level sensing

• Industrial Controls

• Security

• Limit Switching

• Office Equipment

Dimensions

Dimensions in mm (inch)

Low Power > MDSM-4

RoHS

Note: SPST-NO = Single-pole, single-throw, normally open

Note: Land pattern is Littelfuse recommendation only. User is responsible for proper PCB design.

Electrical Ratings

Contact Rating 1W/VA - max. 10

Voltage 3

Switching 2

Breakdown 4

Vdc - max.

Vac - max.

Vdc - min.

200

140

250

Current 3

Switching 2

Carry

Adc - max.

Aac - max.

Adc - max.

0.50

0.35

1.20

Resistance Contact, Initial

Insulation

Ω - max.

Ω - min.

0.100

1010

Capacitance Contact pF - typ. 0.2

Temperature Operating

Storage 5

°C

-40 to +125

-65 to +125

17.52±0.25

(.690±.010)

(.600)MAX

15.24

19.30±0.25

(.760±.010) 2x0.00 MIN

2x2.34 (.092)

2x1.30 (.051)

(.000)

16.00

(.630)

2.84 MAX

(.112)

RECOMMENDED LAND PATTERN

(.039±.004)

1.00±0.10

(.090)MAX

Ø2.28

Notes:

1. Contact rating - Product of the switching voltage and current should never exceed the wattage rating. Contact Littelfuse for additional load/life information.

2. When switching inductive and/or capacitive loads, the effects of transient voltages and/or currents should be considered. Refer to Application Notes AN108A and AN107 for details.

3. Electrical Load Life Expectancy - Contact Littelfuse with voltage, current values along with type of load.

4. Breakdown Voltage - per MIL-STD-202, Method 301.

5. Storage Temperature - Long time exposure at elevated temperature may degrade solderability of the leads.

Note: Contact Littelfuse for specific agency approval ratings.

Speciﬁcations are subject to change without notice.

MDSM-4 R - 17-23

Series

AT Range

12-18 AT

12-23 AT

17-23 AT

17-28 AT

22-28 AT

22-33 AT

27-33 AT

27-38 AT

32-38 AT

Example:

17-23 AT product in Bulk

packaging is MDSM-4B-17-23

Packaging

R = Tape and Reel

B = Bulk

Note: These AT values are the before-modification values of the bare reed switch.

Drop-Out vs. Pull-In Chart

Packaging

Packaging Option Packaging Specification Quantity Quantity and Packaging Code Taping Width

Tape and Reel EIA-RS-481-1 3000 R 32mm

Bulk N/A 200 B N/A

Part Numbering System

Notes:

1. Operate (including bounce)/Release Time - per EIA/NARM RS-421-A, diode suppressed coil (Coil II).

2. Shock and Vibration - per EIA/NARM RS-421-A and MIL-STD-202.

3. Pull-In Range - Contact Littelfuse for narrower AT ranges available. These AT values are the before modification AT of the MDCG-4.

4. Rating Sensitivity - The value at which contact ratings and operating characteristics are determined. Derating may be required below this value.

Surface Mount Reed Switches

Low Power > MDSM-4

MDSM-4 15.3mm Surface Mount Reed Switch

Note: Chart represents the range of Drop-Out, min to max, for a given Pull-In value of

the MDCG-4 prior to modification into the MDSM-4.

Product Characteristics

Operating Characteristics

Operate Time 10.6ms - max.

Release Time 10.2ms - max.

Shock 211ms 1∕2 sine wave 100G - max.

Vibration 250-2000 Hertz 30G - max.

Resonant Frequency 3.9kHz - typ.

Magnetic Characteristics

Pull-In Range 3Ampere Turns 12-38

Rating Sensitivity 4Ampere Turns 20

Test Coil L4989

Drop-Out (AT, L4989 Coil)

Pull-In (AT, L4989 Coil)

10 15 20 25 30 35

Max.

Min.

Speciﬁcations are subject to change without notice.

TAPE DIMENSIONS mm (inch)

REEL DIMENSIONS mm (inch)

MDSM-4 15.3mm Surface Mount Reed Switch

Surface Mount Reed Switches

Low Power > MDSM-4

4,00

2,00

(.079)

(.157)

Ø1,50

-0

(.059

)

067 )

Ø1,70

+.004

+0,10

-0

-.002

+.006

-0,05

+0,15

(.240)

6,10

Ø2,00

1,17

(.046)

(.075)

1,90

7.5°

2,82

(.111)

3.0°

(.240)

6,10

(.084)

2,13

(.315)

8,00

(.069)

1,75

(.559)

14,20

(.079)

28,40

(1.118)

(.059 )

Ø1,50

+.004

+0,10

-0

2. ALL POCKET DIMENSI

ONS ARE ±(.004") 0,10mm

3. ALL DIMENSIONS ARE TO INSIDE OF POCKET

1. ALL TAPE & SPROCKET HOLE DIMENSIONS

ARE PER EIA-481 UNLESS NOTED

(.016)

0,41

32,00

(1.260)

7.5°

(.670)

17,02

(.830)

21,08

120° TYP.

1,9±0.4 TYP.

(.075±.016)

Ø21,0±0.4

Ø13,0±0.2

(.512±.008)

(.827±.016)

(1.276 )

MEASURED AT HUB

+.008

+0.2

(32,4 )

-0

38,4 MAX.

(1.512)

(12.992

)

330,00

(3.937±.020)

100,0±0,50 +0,2

-0,76

+.010

-.030