Push buttons are the most fundamental input components in electronics. Whether you are building a simple LED circuit or a complex industrial control panel, understanding push button types — momentary, latching, and toggle — will help you choose the right component for your project.
Momentary Push Buttons
A momentary push button stays active only while you press it. Release the button and the circuit returns to its default state. This is the most common type you will encounter in electronics projects.
How Momentary Buttons Work
Inside a momentary button, a spring holds the contact apart (or together, for NC types). When you push the button, the contacts make (or break) the connection. The moment you release it, the spring returns the mechanism to its rest position.
Common Uses
- Arduino project inputs (reset, mode select)
- Doorbells
- Game controllers
- Start buttons on machines
- Keyboard keys (every key on your keyboard is a momentary switch)
The humble 6x6mm tactile push button is the workhorse of the maker community — available from as little as ₹2 per piece on Zbotic.
Latching Push Buttons
A latching push button (also called a maintained or self-locking button) stays in its pressed position until you push it again. Think of it like a click-pen mechanism: press once to turn on, press again to turn off.
Internal Mechanism
Latching buttons use a cam or ratchet mechanism. The first press locks the contact in place. The second press releases the cam, and the spring pushes the button back to its rest position.
Common Uses
- Power on/off buttons (computer chassis, power strips)
- Indicator switches on control panels
- Simple ON/OFF circuits where a toggle switch is too large
Toggle Switches
A toggle switch uses a lever or bat handle that you flip between two or three positions. Each position connects a different circuit path. Toggle switches are inherently latching — they stay in the position you set them to.
Position Variants
- ON-OFF — Two positions: one connects the circuit, the other disconnects.
- ON-ON — Two positions, both active. Each connects a different circuit path.
- ON-OFF-ON — Three positions: two active positions with a centre-off resting position.
- (ON)-OFF-(ON) — Momentary on both sides, spring-return to centre-off. Used for motor direction control.
SPST, SPDT, and DPDT Explained
These acronyms describe the internal contact configuration of any switch:
| Type | Full Form | Pins | Description |
|---|---|---|---|
| SPST | Single Pole Single Throw | 2 | Simple on/off |
| SPDT | Single Pole Double Throw | 3 | One input, two output options |
| DPST | Double Pole Single Throw | 4 | Two independent on/off circuits |
| DPDT | Double Pole Double Throw | 6 | Two inputs, two output options each |
Normally Open vs Normally Closed
Normally Open (NO) means the circuit is disconnected at rest. Pressing the button closes the circuit. Most tactile push buttons are NO.
Normally Closed (NC) means the circuit is connected at rest. Pressing the button breaks the circuit. NC buttons are common in safety systems — if the wiring fails, the system defaults to a safe state.
Many industrial-grade push buttons include both NO and NC contacts in a single housing, giving you flexibility in wiring.
Choosing the Right Button for Your Project
- Arduino input / breadboard prototype — 6x6mm tactile momentary button (NO). Cheap, compact, and easy to debounce in software.
- Power on/off — Latching push button or rocker switch. Panel-mount styles look professional.
- Motor direction — DPDT toggle switch or (ON)-OFF-(ON) momentary toggle.
- Control panel — Metal anti-vandal buttons with LED ring for status indication.
- Safety critical — NC emergency stop (mushroom head) button.
Recommended Products from Zbotic
Tactile Push Button Switch 6x6x5mm (Pack of 10)
Red PBS-11A 12MM 2PIN Self-Locking Round Plastic Push Button Switch
5A 3 Pin SPDT Toggle Switch
Mini Panel Mount DPDT Toggle Switch (Pack of 5)
7 Values 70pcs Tact Switch Tactile Push Button Switch Kit
Frequently Asked Questions
What is the difference between a push button and a switch?
Technically, a push button is a type of switch. The term “push button” specifically refers to switches activated by pushing a plunger or button. Other switch types include toggle, rotary, slide, and rocker.
How do I connect a push button to Arduino?
Connect one leg to a digital pin and the other to GND. Enable the internal pull-up resistor using pinMode(pin, INPUT_PULLUP). The pin reads LOW when pressed and HIGH when released.
What is switch bouncing?
When a mechanical switch closes, the metal contacts literally bounce several times before settling. This can cause multiple false triggers. You can debounce in hardware (RC filter) or software (delay/millis-based).
Can I use a momentary button as a toggle in software?
Yes. Use a flag variable in your code that flips each time the button is pressed. This turns a momentary button into a software-defined toggle.
Shop Push Buttons and Switches
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