Axial Lead Reed Switches
Low Power > MDCG-4

MDCG-4 15.3mm Sub-miniature Reed Switch
RoHSDescription
The MDCG-4 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 ofswitching 200Vdc at 10W. It has high insulation resistance of 1010 ohms
minimum and contact resistance less than 100 milli-ohms. This reed switch isalso available in a surface mount version, that is, MDSM-4.

Features• Sub-miniature normallyopen switch• Available sensitivity 12-38 AT

Agency Approvals
AgencyBenefits

Agency File Number

Ampere-Turns Range

E47258E471070

12-38 AT

• Hermetically sealed switch
contacts are not affected by andhave no effect on their external
environment

Note: Contact Littelfuse for specific agency approval ratings.

Applications

Dimensions• Reed Relays• Security• Limit Switching

Dimensions in mm (inch)
CL OF OVERLAP
20.19(.795) REF.

12.19(.480) MIN.

• Capable of switching 200Vdc or
0.5A at up to 10W

0.50(.020) DIA. REF.
2.28(.090) DIA. MAX.

15.24(.600) MAX.

• Zero operating power required forcontact closure• Excellent for switching microcontroller logic level loads• Level Sensing• Office Equipment• Industrial Control

Switch TypeContact Form

A (SPST-NO)

Materials

Body: Glass
Leads: Tin-plated Ni-Fe wire

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

40.38
(1.590) NOM.

Electrical Ratings
Contact Rating 1

W/VA - max.

10

Vdc - max.
Vac - max.
Vdc - min.

200
140250Carry

Adc - max.
Aac - max.
Adc - max.

0.50
0.35
1.20

Contact, Initial
Insulation

Ω - max.
Ω - min.

0.1001010

CapacitanceContactpF - typ.

0.2

Temperature

OperatingStorage 5°C°C-40 to +125
-65 to +125

Switching 2
Voltage 3
Breakdown 4
Switching 2
Current 3
Resistance

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.11/25/20
Specifications are subject to change without notice.

littelfuse.com

Axial Lead Reed Switches

Low Power > MDCG-4

MDCG-4 15.24mm Sub-miniature Reed Switch

Product Characteristics
Operating Characteristics
Operate Time 1

0.6ms - max.

Release Time

0.2ms - max.

Shock12Vibration

11ms 1∕2 sine wave

100G - max.

50-2000 Hertz

30G - max.

2Resonant Frequency

3.9kHz - typ.

Magnetic Characteristics
Pull-In Range 3Rating Sensitivity

4Ampere Turns

12-38

Ampere Turns

20

Test CoilL4989

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.
4. Rating Sensitivity - The value at which contact ratings and operating characteristics are determined. Derating may be required below this value.
5. Custom modifications of forming and/or cutting of reed switches are available. Please contact Littelfuse.

Drop-Out vs. Pull-In Chart

Part Numbering System

30

MDCG-4 -12-18

Drop-Out (AT, L4989 Coil)

25Max.

20

Series15Min.

10

500

51015

20

25

30

35

40

Pull-In (AT, L4989 Coil)

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

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:12-18 AT product is
MDCG-4-12-18

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

Packaging
Packaging Option

Packaging Specification

Quantity

Quantity & Packaging Code

Taping WidthBulk

Bulk

1000

N/A

N/A© 2020 Littelfuse
Revised: BO.11/25/20
Specifications are subject to change without notice.

littelfuse.com