Saleae Logic Analyser

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What is the Logic 8?

The Saleae Logic 8 is a compact, USB-powered logic analyser (with limited mixed-signal oscilloscope functionality) designed for capturing and analysing digital signals—and, to a certain extent, analogue signals. It connects to your computer via USB and uses Saleae’s proprietary software to display, record, and decode various communication protocols (SPI, I²C, UART, CAN, etc.) as well as analogue waveforms.

The Saleae Logic 8 Analyser was donated as part of the Love Essex Fund in 2025.

As part of the purchase, the following was provided:

Wire Harness - 2x4 to Test Clips (Channels 0-3)

Wire Harness - 2x4 to Test Clips (Channels 4-7)

Test Clips 8-Pack (Gen 2)

Logic-to-2x4 Header (Gen 2)

Nano-size Test Clip - for leads < .025 inch diameter (< .64 mm) (x4)

Key Functions

Logic 8
Inputs
Multi-Use (A/D/Both) 8
Digital
Sample Rate (max) 100 MS/s
Fastest Digital Signal 25 MHz
Sample Depth (max) 10+ Billion
Supported Logic Levels 1.8 V – 5.5 V
Works with RS‑232, 422/3, 485 Yes
Analog
Sample Rate (max) 10 MS/s
Bandwidth (3 dB) 5 MHz
Input Range ±5 V
Input Voltage Range 0 V to 5 V
Included
Test Lead Set x2
Test Clips 8‑Pack x2
USB Cable and Carry Case Yes
Physical
Size 2.1″ × 2.1″ × 0.46″ (53 × 53 × 12 mm)
Weight 2.1 oz (60 g)
USB Yes
USB Type USB 2.0
  • Digital Signal Capture

It can sample up to eight channels of digital data at speeds of up to 100 MS/s, enabling you to observe and debug digital circuits in (near) real-time.

  • Analogue Monitoring

In addition to digital signals, the Logic 8 can capture analogue waveforms at up to 10 MS/s (with a 5 MHz bandwidth). Whilst it isn’t a fully featured oscilloscope, it can help with basic analogue signal observation.

  • Protocol Decoding

The Saleae software automatically decodes many common communication protocols (SPI, I²C, UART, etc.), which saves considerable time when troubleshooting complex serial data.

Built-In Protocol Decoding & Analysis

Standard oscilloscopes can display waveforms but often require expensive software add-ons for protocol decoding. The Logic 8 software includes decoders for many protocols, making it far simpler to pinpoint exactly where digital communication issues occur.

  • Deep Memory & Extended Capture Times

Many logic analysers (including the Logic 8) can record a large number of samples (10+ billion, limited mainly by your PC’s memory), allowing long-duration captures. By contrast, standalone oscilloscopes often have more limited onboard memory, restricting the length of time you can record at high sample rates.

  • Portable, Compact Design

The Logic 8 is very small and lightweight—easy to slip into a laptop bag. This portability is particularly advantageous if you move between different workstations or need to debug in the field.

  • Computer Integration & User-Friendly Software

Because the device is controlled via your computer, you can make use of a larger screen, intuitive zoom and scroll controls, and straightforward data saving/sharing. Saleae’s software is known for being easy to use and offers features such as advanced searching, markers, and triggers to streamline debugging.

When a traditional oscilloscope might still be preferable

High-Frequency Analogue Signals: If you need to measure signals beyond the Logic 8’s bandwidth or you require detailed analogue analysis (e.g., sub-nanosecond rise times), a high-bandwidth oscilloscope is more appropriate.

Precise Analogue Measurements: Oscilloscopes typically provide a higher-resolution vertical scale, multiple input ranges, and better signal integrity for in-depth analogue analysis.