Reed Switches Datasheet

MISM-77mm Surface Mount Reed Switch
RoHSDescription
The MISM-7 surface mount reed switch is a sub-miniature,normally open switch with a 7mm long x 1.8mm diameter (0.276”x 0.071”) glass envelope, capable of switching up to 0.25 Amps.
This reed switch is a surface mount version of the MITI-7. It has ahigh insulation resistance of 1012 Ohms minimum and a contact
resistance of less than 150 milliohms.

Features & Benefits■ Ultra-miniature surface mountnormally open switch■ Available sensitivity range
6-10 AT■ Capable of switching 170 Vdc
or 0.25A up to 10W■ Hermetically sealed switch
contacts are not effected byand have no effect on theirexternal environment

Additional Information■ Zero operating power
requiredfor contact closure■ Excellent for switching
microcontroller logic levelloads■ Very low space requirement

Applications
Resources

Accessories

Samples■ Position Sensing■ Security■ Level Sensing■ Office Equipment■ Meter Equipment

Agency Approvals
AgencySwitch Type

Agency File Number

Ampere-Turns Range

Contact Form

A (SPST-NO)

E47258E471070

6 - 20ATMaterials

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

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

Note: Contact Littelfuse for specific agency approval ratings.

Electrical Ratings
Contact Rating 1

W/VA - max.

10Voltage 3

Switching 2
Breakdown 4

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

170
120
175

Current 3

Switching 2
CarryAdc - max.
Aac - max.
Adc - max.

0.25
0.18
0.50

ResistanceContact, Initial
Insulation

Ω - max.
Ω - min.

0.150
1012

CapacitanceContactpF - typ.

0.3

Temperature

OperatingStorage 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.

1© 2021 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: GD.07/12/21

Reed Switches Datasheet

MISM-77mm Surface Mount Reed Switch

Product Characteristics
Operating Characteristics

Operate Time
Release Time 1
Shock 2Vibration 2
Resonant Frequency

11ms 1∕2 sine wave
50-2000 Hertz-10.45ms - max.
0.20ms - max.
100G - max
30G - max.
14kHz - typ.

Magnetic Characteristics

Pull-In Range
Rating Sensitivity 4
Test CoilAmpere Turns
Ampere Turns-36-10, 10-15, 15-20
10L4991

Notes:
1. Operate (including bounce)/Release Time - per EIA/NARM RS-421-A, diode suppressed coil (Coil I).
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 MITI-3V1.
4. Rating Sensitivity - The value at which contact ratings and operating characteristics are determined. Derating may be required below this value.

Drop-Out vs. Pull In Chart

Part Numbering System

25MISM-7 R - 6-10

Drop-Out (AT, L4991 Coil)

20SeriesMax.
15Packaging
R = Tape and Reel
B = Bulk

Min.
10FormBlank = 13.72mm
5 = 12.60mm

5AT Range
6-10 AT
10-15 AT
15-20 AT00510152025

Pull-In (AT, L4991 Coli)

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

Example: 6-10 AT product is MISM-7R-6-10

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

Packaging
Packaging Option

Packaging Specification

Quantity

Quantity and Packaging CodeTaping Width

Tape and Reel

EIA-RS-481-1

3000R32mm

2© 2021 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: GD.07/12/21

Reed Switches Datasheet

MISM-77mm Surface Mount Reed Switch

Dimensions
Dimensions in mm
2x .84 ± .10
2x 1.91 ± .10

2X 3.25 TYP

2X 1.12 TYP(1.64)

8.60

1.64

7.00 Max
1.53

2.28 Max

6.86±.51

2x 1.00 ± .15

Recommended Land Patternø1.80 Max
Leads Need to be Flat ±5°.15.02 Min

+.00
- .25
+.00
13.72
- .25
9.90

Recommended Land Pattern

2x 1.20 ± .10(1.66)

1.66

7.00 Max
1.72

2.28 Max

2X 3.25 TYP

2X 1.128.60

ø1.80 Max
Leads Need to be Flat ±5°.15.02 Min
6.35±.60
10.20 ± .30
12.60 ± .30

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

Tape Dimensions mm (inch)

Reel Dimensions mm (inch)

Disclaimer Notice - Information furnished is believed to be accurate and reliable. However, users should independently evaluate the suitability of and test each product selected for their own applications. Littelfuse products are
not designed for, and may not be used in, all applications. Read complete Disclaimer Notice at www.littelfuse.com/disclaimer-electronics.
© 2021 Littelfuse, Inc.
3
Specifications are subject to change without notice.
Revised: GD.07/12/21