Name: Keyboard PCB
Brand: PCB Printed Circuit Board and PCBA manufacturing
Rating: 5 (1 reviews)

Description
Data Sheet

Keyboard PCB is the core circuit board of computer and electronic device keyboards. It is specially designed to detect key triggering, identify key coordinates, and transmit key data to connected hosts and terminals.

Basic Composition & Working Principle

A standard keyboard PCB consists of two core circuit parts to realize on-off signal feedback for key actions. When a key is pressed, the internal circuit completes connection or disconnection, feeding coordinate signals to the onboard keyboard controller.

The PCB is integrated with a dedicated microprocessor (keyboard controller), ROM chip for key code storage, and hardware interface modules. The ROM solidifies the mapping relationship between key positions and character codes. Common external transmission interfaces include USB, serial port and wireless modules.

Main PCB Materials for Keyboards: Conventional rigid FR4 PCB and flexible FPC flexible circuit board, meeting thin, lightweight and bending-resistant design requirements for different keyboard structures.

Two Key Sensing Principles

Conductive Contact Sensing
A small conductive contact pad is arranged under each key. Pressing the key connects the PCB circuit, and the controller captures the key position signal. It then matches the preset code table in ROM to output corresponding character commands. This solution is widely used in membrane and mechanical keyboards.
Capacitive Sensing
Also defined as capacitive keyboard solution, stable electrical signals continuously circulate on the complete keyboard circuit matrix. Each key is equipped with an induction plate; pressing changes the electrode distance and ambient capacitance, causing real-time current fluctuation. The controller captures capacitance changes to identify key actions, featuring contactless triggering and low wear.

Keyboard Classification by Coding Mode

Full-Coding Keyboard

Equipped with independent hardware decoding and matrix switching chips. The single-chip microcomputer completes key scanning and encoding independently, and only transmits standard coded data to the host.

Features: Fast response, full anti-ghosting, no key conflict; however, the hardware structure is complex and costly, and it is rarely used in civilian products currently.

Non-Coding Keyboard

Relying on host software and driver programs to complete key scanning, decoding and data transmission.

Features: Slightly slower response and partial key conflict limitations; supports software key customization and function expansion, with low cost and strong compatibility, occupying the mainstream market.

Keyboard Main Program Logic

The main program calls the scanning module to traverse the row-column key matrix and obtain key coordinate scanning codes;
Transmit valid scanning codes to the host interface circuit;
Complete data decoding and convert scanning codes into standard character codes;
The interface module uploads the final encoded information to the terminal host.

Classification by Connection Interface

Wired: PS/2 round port, USB interface
Wireless: 2.4G receiver, Bluetooth wireless mode

Keyboard

Common Keyboard Types & Structural Differences

Mechanical Keyboard

Each key is equipped with an independent mechanical switch (mechanical shaft), adopting metal contact conduction.

Advantages: Clear typing feedback, unchanged hand feel after long-term use, strong durability (single-key life up to 50 million strokes), full-key anti-ghosting support, customizable keycaps and DIY modification; suitable for office typing and gaming scenarios.

Disadvantages: High noise, high cost and complex assembly.

Membrane Keyboard

Multi-layer plastic film integrated structure with conductive rubber contact design, no mechanical shaft wear.

Advantages: Low noise, low cost, soft pressing feel, good durability and high cost performance; dominating the civilian keyboard market.

Disadvantages: The pressing feel will degrade after long-term compression, and the anti-ghosting capability is weak.

Capacitive Keyboard

High-end contactless solution, triggering by capacitance change between electrodes.

Advantages: Ultra-light pressing feel, sensitive response, zero mechanical wear, excellent sealing and dustproof performance;

Disadvantages: Expensive, low market popularity, mainly produced by a few professional manufacturers.

Conductive Rubber Keyboard

A transitional product between mechanical and membrane keyboards, adopting convex conductive rubber for contact conduction. It has been gradually phased out in the consumer market.

Professional Keyboard PCB Manufacturing | Maxipcb

Keyboard PCB requires stable circuit conductivity, dense line layout and long-term anti-fatigue performance.

Maxipcb provides one-stop services for keyboard PCB prototype proofing, small-batch trial production and mass production. We support FR4 rigid boards and FPC flexible boards, with mature processes for membrane keyboards, mechanical keyboards and capacitive keyboard circuit boards to meet customized design demands.

Model: Keyboard PCB

Material: FR-4, PI, Aluminum

Layer: 2Layer

Color: Blue/White/Black/Green

Finished Thickness: 1.0-1.2mm

Copper Thickness: 1OZ

Surface Treatment: OSP

Min Trace: 6mil

Min Space: 6mil

Application: Keyboard

Keyboard PCB

Description

Data Sheet