Point of Sale

In retail and hospitality environments, a POS (Point of Sale) system is far more than just a computer; it acts as a sophisticated communication hub integrating various peripheral devices. To ensure transaction stability, touch responsiveness, and real-time synchronization with peripherals (such as receipt printers and barcode scanners), POS hardware demands rigorous specifications for connectors and cabling.

The following are the primary categories of connectors and cables used in POS systems:

1. Internal Core Connections (PCB & Display)

These connectors are located inside the chassis, handling signal transmission between the motherboard, the display, and the touch panel.

  • FPC/FFC Connectors: Used to connect the LCD panel and the touch layer. As POS designs trend toward slim profiles and narrow bezels, 0.5mm or 1.0mm pitch connectors are the industry standard.

  • LVDS / eDP Cables: Responsible for high-resolution image transmission. eDP (Embedded DisplayPort) is increasingly favored for high-end touch POS screens due to its superior bandwidth.

  • Board-to-Board (BTB) Connectors: Used to link the motherboard with I/O expansion boards, facilitating a modular design that simplifies maintenance.

2. External Peripheral Interfaces (I/O Interfaces)

POS machines must support a vast array of external devices, resulting in a highly diverse set of rear I/O ports.
 

Device Type Connector / Cable Description
Cash Drawer RJ11 / RJ12 The most common interface, typically triggered by a signal from the receipt printer.
Receipt Printer / Scanner USB Type-A / Type-C The modern standard; Type-C can simultaneously handle data and power delivery.
Legacy Peripherals / Scales DB9 (RS232) Many industrial or legacy devices still rely on serial communication for high stability.
Customer Display / Secondary Screen HDMI / VGA Used to display transaction information to the customer.
Network Connectivity RJ45 (Ethernet) Ensures stable connections for electronic payments and cloud-based inventory systems.
 

3. Specialized Cable Specifications: PoweredUSB

PoweredUSB (also known as Retail USB) is a unique technology specific to the POS industry. While standard USB provides only 5V, POS peripherals (like large thermal printers) often require 12V or 24V.

￭ The Design: This cable adds a separate set of power contacts above the standard USB interface.

￭ The Advantage: It allows peripherals to operate without individual power adapters. A single cable handles both data transmission and high-wattage power, significantly reducing cable clutter behind the counter.

4. Wire Harness Processing and Protection

Because POS systems are often exposed to humidity (in kitchens/restaurants) or frequent vibration (in mobile POS units), their internal wire harnesses require:

  1. Bending Resistance Tests: Critical for flip-style or adjustable-angle screens.

  2. EMI Shielding: Prevents electromagnetic interference from causing "ghost touches" on the screen.

  3. PE Film Protection: Provides insulation and physical reinforcement for FFC (Flexible Flat Cables).

Technical Note: Modern POS systems are gradually shifting toward USB Type-C (Power Delivery) integrated solutions. In the future, this may replace traditional dedicated power cables and PoweredUSB, achieving broader device compatibility.