Cherry MX

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Template icon--Illustration.png This article requires additional photographic illustration — need photo of opened switch with diode (for this and the diode page) and photos showing PCB-mount variants (alone and vs plate mount)
Cherry MX
Cherry MX scale.svg
Family Cherry MX
Introduced 1983-11-07
Keycap mount Cherry MX mount
Hirose Cherry mount
Alps mount
Switch mount PCB mount
plate mount
Patents US4467160 (1983)
Different variants of the Cherry MX switch
Cherry MX shipping boxes
A keyboard with MX Blue switches
MX switches with Hirose Cherry branding and keycap mount

Cherry MX is a type of microswitch used in computer keyboards. It is the most popular switch used in mechanical keyboards. Various types are available, each with a different key feel. They were introduced by Cherry on 7 November 1983[1] and were at first only available in their linear variant. It is most common to refer to the various variants of MX switches based on their stem color, though Cherry officially does not use the color for identification.

Design

Cherry MX switches use gold crosspoint contacts. The contact mechanism has one small static terminal, and a movable leaf that is folded against itself at the top. At least two designs of contact mechanism are known. As of 2013, the current system has a very narrow "neck" where it folds back on itself. One known previous design uses more metal and appears to be more complicated; this design has been found in the Hirose Cherry MX Orange[2] and Hirose Cherry MX Clear, as well as Cherry MX Black.[3]

All German Cherry MX switches, and some Japanese-made Hirose MX switches, are branded "CHERRY" on the top; the exact logo used has varied over time. Hirose MX switches were also branded "HCP" (Hirose Cherry Precision).

The design principal of the shell is based on the Cherry M9. The upper shell cannot be removed while the switch is mounted in a plate; the switch must first be desoldered and removed from the plate before it can be opened. The four retention clips that hold the upper shell in place need to move outwards, and the hole in the plate blocks this. For modification purposes, a PCB-mount keyboard is preferred, or an enthusiast-created plate with four small cutouts designed to allow the switches to be opened in-place.

Clicky switches use a special two-piece slider; the movable contact fires the "click collar" downwards on passing the actuation point, generating a click sound. The click collar is pulled back upwards on the return stroke by the slider itself, and held in place by the movable contact.

The keycap mount is only 180° rotationally symmetrical. The horizontal (E and W) arms of the cross are around 1.25–1.30 mm thick, while the vertical (N and S) arms of the cross are around 1.05–1.10 mm thick; there is a difference of around 0.2 mm. Keycaps do not always fit sideways. The stem on the keycap is around 3.7 mm tall; it sits on a platform that descends inside the switch, so the full travel is able to be greater than the stem height.

Variants

Force-Travel diagram (CN / mm) for the downstroke of the most common Cherry MX switches

Common variants

The most common variants of the Cherry MX keymodule are black and red for the linear switches and clear, brown and blue for the tactile switches along with various variants such as green and (tactile) grey, which are usually only used in space bars.

Hirose Cherry

Hirose Cherry Precision ("Cherry Japan") manufactured a version of the MX switch with the Hirose Cherry keycap mount. Hirose Cherry MX switches accept standard Cherry MX keycaps, but Hirose keycaps do not fit on standard switches.

Other variants

Other, more rare variants of the Cherry MX switch are known to include other obscurities such as a transparent switch housing, and allegedly the early MX switches all had clear stems.[4]

Old versions of the blue switches exist. Because no dye was added to the stem's plastic, these switches are called white switches.[Citation needed]

Table of all known variants

Name Product code Type Key feel Actuation Hysteresis Mount Stem cam Production
Cherry MX Black.jpg Cherry MX Black MX1A-11xx Normal Linear 60 cN No MX No Yes
Cherry MX Linear Grey.jpg Cherry MX Linear Grey MX1A-21xx Space bar Linear 80 cN No MX No Yes
Cherry MX Lock.jpg Cherry MX Lock MX1A-31xx Alternate action Linear 60 cN No MX No Yes
Cherry MX white.jpg Cherry MX White MX1A-A1xx Normal Clicky 50 cN/80 cN Yes MX Yes Yes
No photograph.svg Cherry MX Click Grey MX1A-B1xx Space bar Clicky 105 cN Yes MX Yes No
Cherry MX clear.jpg Cherry MX Clear MX1A-C1xx Normal Tactile 65 cN No MX No Yes
Cherry MX Tactile Grey.jpg Cherry MX Tactile Grey MX1A-D1xx Space bar Tactile 80 cN No MX No Yes
Cherry MX Blue.jpg Cherry MX Blue MX1A-E1xx Normal Clicky 50 cN Yes MX Yes Yes
Cherry MX Green.jpg Cherry MX Green MX1A-F1xx Space bar Clicky 80 cN Yes MX Yes Yes
Cherry MX Brown.jpg Cherry MX Brown MX1A-G1xx Normal Tactile 45 cN No MX No Yes
Cherry MX red.jpg Cherry MX Red MX1A-L1xx Normal Linear 45 cN No MX No Yes
No photograph.svg Cherry MX RGB Black MX1A-11xx Normal Linear 60 cN No MX No Yes
No photograph.svg Cherry MX RGB Blue MX1A-E1xx Normal Clicky 50 cN Yes MX Yes Yes
No photograph.svg Cherry MX RGB Brown MX1A-G1xx Normal Tactile 45 cN No MX No Yes
No photograph.svg Cherry MX RGB Red MX1A-L1xx Normal Linear 45 cN No MX No Yes
No photograph.svg Cherry MX Super Black  ? Special Linear 150 cN  ? MX No No
No photograph.svg Cherry MX Translucent  ?  ? Linear  ?  ? MX  ? No
No photograph.svg Cherry MX Yellow  ?  ? Linear  ?  ? MX  ? No
No photograph.svg Cherry MX Pale Grey  ?  ? Linear  ?  ? MX  ? No
No photograph.svg Cherry MX-M8 Adapter  ? Normal Linear  ?  ? M8  ? No
No photograph.svg Hirose Cherry MX Pale Yellow  ? Normal Linear  ?  ? Hirose No No
No photograph.svg Hirose Cherry MX Grey Green  ? Normal Linear  ?  ? Hirose No No
Hirose Cherry MX Orange.jpg Hirose Cherry MX Orange  ? Normal Linear  ?  ? Hirose No No
No photograph.svg Hirose Cherry MX Clear  ? Normal Linear  ?  ? Hirose No No
No photograph.svg Cherry MX Alps Click  ?  ? Clicky  ? Yes? Alps N/A No
No photograph.svg Cherry MX Alps Linear  ?  ? Linear  ?  ? Alps N/A No

Recombination variants

This switch versions can be created by recombining stems and springs from existing Cherry MX switches

Features (as advertised by Cherry)

  • Desktop profile, 0.60 inch (15.2 mm) from PCB (no keycap)
  • Choice of feel: linear, soft tactile, click tactile
  • PCB or frame mount
  • Long life 20–50 million operations (depending on switch variant)
  • 4 mm travel
  • LED, diode or jumper option
  • 12V maximum AC/DC
  • Current Rating: 10 mA
  • Insulation Resistance: < 100 MΩ at 100V DC

Mounting options

Cherry MX switches offer additional mounting options for either a wire bridge, a LED or a diode. Cherry offers all three variants and a fourth without any special options directly on their wholesale orders. Switches are available for either PCB or plate mounting, the main difference being that switches intended for PCB mounting have two additional plastic pins that secure and stabilize them when being mounted on the PCB. Plate mounted switches do not necessarily need these extra pins, since they are already being stabilized by the metal backplate. PCB mounted switches can be easily converted for back plate mounting by simply cutting off their extra stems. The mounting options are described by the final two digits of the product number (see below).

Product numbers

Key switches in the Cherry MX series follow an eight digit naming convention: M X [1,5] [A,C] - [0-9, A-Z] [1] [N,R,G,Y,D,J] [N,W,A,B]

  • M: Keyswitch module
  • X: Cherry MX family
  • [1,5]
    • 1: Material: AuAg10, 10mA, max. 12V
    • 5: Special
  • [A,C]
    • A: SPST NO (single pole, single throw, normally open)
    • C: Special
  • [0-9, A-Z] — Operating characteristics, actuating force and key style (the switch 'color'):
  • [1,A-Z] — Keystem configuration
    • 1: Standard straight, cross-shaped keystem for standard Cherry key caps (the Cherry MX mount)
    • G: Special (Germany) with D and H reserved for future use
    • W: Special (USA) with C and F reserved for future use
    • U: Special (UK) with K and E reserved for future use
    • N: Special (Japan) with J and L reserved for future use
    • A: Special (Australia) with Q and M reserved for future use
    • B: Special (Brazil) with S and P reserved for future use
  • [N,R,G,Y,D,J] - Integrated components
    • N: No additional, integrated components
    • R: Red LED
    • G: Green LED
    • Y: Yellow LED
    • D: Diode
    • J: Jumper wire
  • [N,W] - Mounting configuration / case color
    • N: No plastic mounting pins (plate mount) / black case
    • W: With plastic mounting pins (PCB mount) / black case
    • A: No plastic mounting pins (plate mount) / clear case
    • B: With plastic mounting pins (PCB mount) / clear case

The following examples demonstrate possible Cherry MX product numbers and their descriptions:

  • MX1A-11NN - Cherry MX Black/linear, no diode, plate mount (no fixing pins)
  • MX1A-E1DN - Cherry MX Blue/tactile clicky, with diode, plate mount (no fixing pins)
  • MX1A-L1RW - Cherry MX Red/low-force linear, red LED, PCB mount (with fixing pins)
  • MX1A-G1JW - Cherry MX Brown/tactile non-clicky, with jumper wire, PCB mount (with fixing pins)

Disassembly

The Cherry MX switch shell is based on that of Cherry's earlier M9 switch, their previous low-profile switch ("low-profile" in the 80s being standard profile from the 90s onwards).

Cherry MX switches cannot be opened when the switch is mounted into a plate. For PCB-mounted switches, the shell can be opened using the four corner holes. Insert a screwdriver into two opposite corner holes, and pry the side retention tabs away from the switch body. This is not possible with the plate in place as the plate prevents the side tabs from moving outwards to clear the retaining lugs.

  • Opening one side of the switch

Gallery

Accessories

  • MX switch with LED fitted

  • MX switch with jumper fitted

  • Switches with LEDs fitted require diodes to be external

Design

  • Base

  • Front

  • Rear

  • Variant design used for windowed keycaps on certain Cherry models such as the G80-3700HAU/04

  • Hirose Cherry MX switch with original HCP branding

Construction

  • Sliders and springs

  • Click sliders from blue and white switches

  • MX Blue and opened MX Brown

  • Partially disassembled switch

  • Gold crosspoints

  • Electrical contacts (2013 switch)

  • Contact plate and leaf (2013 switch)

  • Fully disassembled MX Brown (top views)

  • Fully disassembled MX Brown (bottom views)

See also

External links

References

  1. ↑ Deskthority — 7 November 1983-2013 | 30 Years Cherry MX!
  2. ↑ ちゃたりたいね — Yamaha QX3 Sequencer keyboard
  3. ↑ geekhack — This cherry switch
  4. ↑ Deskthority — Hirose Cherry switches and the Xerox 1109
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