J-Link BASE
J-Link BASE is a USB-powered JTAG debug probe supporting a large number of CPU cores. Based on a 32-bit RISC CPU, it can communicate at high speed with the supported target CPUs. J-Link is used around the world in tens of thousand places for development and production (flash programming) purposes.
The J-Link debug probes are supported by all major IDEs including Eclipse, GDB-based IDEs and SEGGER Embedded Studio. For a complete list, please refer to supported IDEs. Including all models, more than 1,000,000 J-Links have been shipped so far, making J-Link probably the most popular debug probe for Arm cores and the de-facto standard.
Key features
- Download speed up to 1 MB/s
- Built-in VCOM functionality
- Supports a broad range of microcontrollers
- Free software updates
License upgrade
The J-Link BASE offers basic functionality. To use the full range of functions of a J-Link PLUS, for instance, the J-Link Upgrade BASE to PLUS is needed.
This license upgrade comes with a software bundle that includes the J-Flash / J-Flash SPI license, software to program EEPROM and flash chips in Arm systems, as well as a J-Link Unlimited Flash Breakpoints license. Included is also the Ozone J-Link Debugger & Performance Analyzer, the Monitor Mode Debugging technology, the J-Link RDI / RDDI license, and the license pack for the RDI / RDDI interface.
Multi-platform
As a multi-platform solution, J-Link BASE comes with the setup and control software for Linux, macOS and Windows. Software and firmware updates are included. Similarly, use on all currently supported target devices, and any that will be added, is also included.
Technical specifications
General | |
Supported OS | Microsoft Windows (x86/x64), Linux (x86/x64/Arm), macOS (x86/Apple Silicon) |
Electromagnetic compatibility (EMC) | EN 55022, EN 55024 |
Operating temperature | +5°C … +60°C |
Storage temperature | -20°C … +65 °C |
Relative humidity (non-condensing) | Max. 90% rH |
Mechanical | |
Size of J-Link BASE Classic (without cables) | 100mm x 53mm x 27mm |
Weight of J-Link BASE Classic (without cables) | 70g |
Size of J-Link BASE Compact (without cables) | 46mm x 46mm x 17mm |
Weight of J-Link BASE Compact (without cables) | 20g |
Available interfaces | |
USB interface (J-Link BASE Classic) | USB 2.0 (Hi-Speed); USB Type B |
USB interface (J-Link BASE Compact) | USB 2.0 (Hi-Speed); Micro USB |
Target interface | JTAG/SWD 20-pin (adapters available) |
JTAG/SWD interface, electrical | |
Power supply | USB-powered Max. 50mA + Target Supply current. |
Target interface voltage (VIF) | 1.2V … 5V |
Current drawn from target voltage sense pin (VTRef) | < 25µA |
Target supply voltage | 5V (derived from USB voltage) |
Target supply current | Max. 300mA |
Reset type | Open drain. Can be pulled low or tristated |
Reset low level output voltage | VOL <= 10% of VIF |
For the whole target voltage range (1.2V <= VIF <= 5V) | |
LOW level input voltage (VIL) | VIL <= 40% of VIF |
HIGH level input voltage (VIH) | VIH >= 60% of VIF |
For 1.2V >= VIF <= 3.6V | |
LOW level output voltage (VOL) with a load of 10 kOhm | VOL <= 10% of VIF |
HIGH level output voltage (VOH) with a load of 10 kOhm | VOH >= 90% of VIF |
For 3.6 <= VIF <= 5V | |
LOW level output voltage (VOL) with a load of 10 kOhm | VOL <= 20% of VIF |
HIGH level output voltage (VOH) with a load of 10 kOhm | VOH >= 80% of VIF |
JTAG/SWD interface, timing | |
Target interface speed | Max. 50 MHz |
SWO sampling frequency | Max. 30 MHz |
Data input rise time (Trdi) | Trdi <= 20ns |
Data input fall time (Tfdi) | Tfdi <= 20ns |
Data output rise time (Trdo) | Trdo <= 10ns |
Data output fall time (Tfdo) | Tfdo <= 10ns |
Clock rise time (Trc) | Trc <= 3ns |
Clock fall time (Tfc) | Trc <= 3ns |
Assembly dimensions
The compact variant of the J-Link PLUS is designed to mount securely and unobtrusively into development or end user equipment. The small size and two mounting holes enable placing the J-Link PLUS Compact into existing equipment housings or to reserve space for direct-to-PCB mounting.
Typical applications are test fixtures that are used to automate firmware verification during development, or long-term test setups. It also can be used for integrated firmware reflash or service purposes inside end equipment, minimizing the number of tools that service technicians must carry around.

Explosion view of the J-Link BASE Compact

Assembly dimensions of the J-Link BASE Compact
Package content
J-Link BASE Classic



J-Link BASE Classic
USB cable
20-pin, 0.1″ target ribbon cable
J-Link BASE Compact



J-Link BASE Compact
USB cable
20-pin, 0.1″ target ribbon cable