Surface Mount Reed Switches
Low Power > MDSM-4
MDSM-4 15.3mm Surface Mount Reed Switch
RoꢀS
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.
Features
• Capable of switching 200Vdc or
• Surface mount, normally
0.5A at up to 10W
open switch
Agency Approvals
• Available sensitivity 12-38 AT
• Low, stable contact resistance
Agency
Agency File Number
Ampere-Turns Range
Benefits
E47258
E471070
12-38 AT
• Zero operating power required for
contact closure
• Excellent for switching micro-
controller logic level loads
• Hermetically sealed switch
contacts are not affected by and
have no effect on their external
environment
Note: Contact Littelfuse for specific agency approval ratings.
Dimensions
Ø2.28
(.±9±)MAX
1.±±±±.1±
(.±39±.±±4)
Dimensions in mm (inch)
Applications
• Position Sensing
• Level sensing
• Industrial Controls
• Security
• Limit Switching
• Office Equipment
17.52±±.25
(.69±±.±1±)
15.24
(.6±±)MAX
Switch Type
ꢀ.84 MAX
(.11ꢀ)
19.30 0.ꢀ2
(.760 .010)
Contact Form
A (SPST-NO)
ꢀx0.00 MIN
(.000)
Body: Glass
Leads: Tin-plated Ni-Fe wire
Materials
RECOMMENDED LAND PATTERN
ꢀx1.30 (.021)
ꢀxꢀ.34 (.09ꢀ)
Note: SPST-NO = Single-pole, single-throw, normally open
16.00
(.630)
Note: Land pattern is Littelfuse recommendation only. User is responsible for proper PCB design.
Electrical Ratings
Contact Rating 1
W/VA - max.
10
Switching 2
Vdc - max.
Vac - max.
Vdc - min.
200
140
250
Voltage 3
Breakdown 4
Switching 2
Adc - max.
Aac - max.
Adc - max.
0.50
0.35
1.20
Current 3
Carry
Contact, Initial
Insulation
Ω - max.
Ω - min.
0.100
1010
Resistance
Capacitance
Temperature
Contact
pF - typ.
0.2
Operating
Storage 5
°C
°C
-40 to +125
-65 to +125
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.
© 2020 Littelfuse
Revised: BO.12/08/20
littelfuse.com
Specifications are subject to change without notice.