48. Device Address DIP Switch
1. Component Purpose
On an RS-485 bus, every device needs a unique address so the master can communicate with each one individually. A 4-position DIP switch lets the installer set this address manually using 4 binary switches (providing 2⁴ = 16 possible addresses).
Each switch position connects an MCU input to either HIGH or LOW. The MCU reads these 4 pins at startup to determine its bus address. This is a standard approach in industrial control equipment.
Required: SPST · 4 Positions · Slide Actuator · Raised · 2.54mm Pitch · Through Hole
2. How to Find It on DigiKey
Go to DigiKey.com → Switches → DIP Switches
Apply these filters:
- Circuit → SPST
- Number of Positions → 4
- Actuator Type → Slide (Standard)
- Actuator Level → Raised
- Pitch → 0.100" (2.54mm)
- Mounting Type → Through Hole
- Part Status → Active
Tip: "Raised" actuator level means the switch toggles protrude above the body, making them easy to flip with a fingertip or small tool. "Flush" actuators sit level with the body and need a pointed tool.
3. Key Specifications & What They Mean
| Specification | Required | Why |
|---|---|---|
| Circuit | SPST | Each position is a simple ON/OFF. |
| Positions | 4 | 4-bit address = 16 possible addresses. |
| Actuator | Slide, Raised | Easy to toggle manually. |
| Pitch | 2.54mm (0.100") | Standard through-hole IC/header pitch. |
| Current | ≥50mA | Logic-level sensing; minimal current. |
| Voltage | ≥24VDC | Margin for 3.3V/5V logic circuits. |
| Mounting | Through Hole, PC Pin | Standard DIP footprint on PCB. |
| Temp Range | −55°C to +85°C | Industrial operating conditions. |
4. Selecting a Safe, Production-Ready Part
The filtered list will show matching parts. Before you pick one, check: Is it Active? Is stock available? Is the manufacturer reputable? Is a datasheet available?
Full checklist: How to Select a Safe, Production-Ready Component — EWskills Guide