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  • J-Link debug probes
  • J-Link ULTRA+

    J-Link ULTRA+
    The ultra-fast debug probe

    J-Link ULTRA+ is an ultra-fast debug probe for JTAG/SWD. It is 100% compatible with J-Link PLUS, just faster.

    Buy now
    Compare J-Link models
    Documentation
    SEGGER J-Link ULTRA+ debug probe
    1. 1.Key features
    2. 2.Supported devices
    3. 3.Software
      1. 3.1.Multi-platform
      2. 3.2.J-Flash
    4. 4.Speed
    5. 5.Flash Breakpoints
    6. 6.Ozone — The J-Link Debugger
      1. 6.1.Standalone debugger
      2. 6.2.Performance analyzer
    7. 7.Media gallery
      1. 7.1.Product photos
      2. 7.2.Videos
    8. 8.Technical
    9. 9.Package content
    10. 10.FAQ
    11. 11.Latest news

    Overview

    J-Link ULTRA+ is a JTAG/SWD debug probe designed for Arm/Cortex. It is fully compatible to the standard J-Link and works with the same PC software.

    Based on the highly optimized and proven J-Link, it offers even higher speed as well as target power measurement capabilities due to the faster CPU, built-in FPGA and high-speed USB interface.

    Key features

    • Download speed up to 4 MB/s
    • Unlimited breakpoints in flash memory (Flash Breakpoints)
    • Use with Ozone, RDI/RDDI and J-Flash
    • Additional LEDs for power and RESET indication
    • Built-in VCOM functionality
    • Supports a broad range of microcontrollers
    • Supports direct download into RAM and flash memory
    • Free software updates

    Supported devices

    The J-Link ULTRA+ as a member of the SEGGER J-Link debug probes supports a wide range of CPU cores. The list of supported manufacturers, families, and devices and SoCs includes tens of thousands of devices in hundreds of device families.

    Device not listed? Please don’t hesitate to contact us.

    SEGGER Flasher PRO - Icon: Three black puzzle pieces above blue puzzle piece (Universal Target Support)

    Software

    All software is included free of charge. It comes with licenses for all J-Link related SEGGER software products, such as J-Link Unlimited Flash Breakpoints, Ozone, RDI/RDDI, J-Flash, J-Link GDB Server, providing the optimum debugging solution for professional developers.

    The J-Link Software and Documentation Package is available here:

    DownloadJ-Link Software and Documentation Pack

    Multi-platform

    As a multi-platform solution, J-Link ULTRA+ 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.

    J-Flash

    J-Flash is part of the J-Link Software and Documentation Package and allows the programming of the internal and external flash memory of a microcontroller-based embedded system via J-Link.

    Learn more about J-Flash...

    J-Link ULTRA+: J-Flash (icon)

    Speed

    Up to 4 MB/s download speed make J-Link ULTRA+ the fastest debug probe on the market.

    Learn more about flash programming speed...

    J-Link ULTRA+: Speed (icon)

    Flash Breakpoints

    The J-Link ULTRA+ comes with an additional feature, called Unlimited Flash Breakpoints. Unlimited Flash Breakpoints allow the user to set an unlimited number of breakpoints when debugging in flash memory.

    Learn more about Unlimited Flash Breakpoints...

    J-Link ULTRA+: Flash Breakpoints (icon)

    Ozone — The J-Link Debugger

    Ozone is the debugger for J-Link and J-Trace. It includes all well-known debug controls and information windows, and makes use of the best performance of J-Link and J-Trace debug probes.

    Standalone debugger

    Ozone focuses on debugging, with no compiler or project window distractions. All debug windows can be moved, resized and docked, to provide you with the workspace you need.

    Ozone offers all well-known debug controls and information windows, and more. Instruction trace, power graph, live watches, and real-time terminal I/O further extend these capabilities.

    Ozone: Debugging features (screen)
    Debugging with Ozone

    Performance analyzer

    With J-Link's High-Speed Sampling technology, Ozone can sample and visualize an embedded system's variables over time. Checking values and flags in the debugger is easy, while the target keeps running.

    J-Link's power measurement features enable you to record the power consumption of your target device in a debug session. This is especially helpful when you develop a low-power device and need to know how power consumption changes when you enable or disable certain components.

    Ozone: Performance analysis features (screen)
    Performance analysis with Ozone

    Media gallery

    Product photos

    SEGGER J-Link ULTRA+ debug probe
    J-Link ULTRA+ front
    SEGGER J-Link ULTRA+ host connector
    J-Link ULTRA+ host connector
    SEGGER J-Link ULTRA+ target connector
    J-Link ULTRA+ target connector

    Videos

    SEGGER J-Link Tutorials: The J-Link Configurator

    Mar. 2022 | 5:24 min
    J-Link — J-Link Configurator

    SEGGER J-Link Tutorials: The J-Link Commander

    Mar. 2022 | 7:48 min
    J-Link — J-Link Commander

    SEGGER J-Link Remote Server: Accessing a J-Link, J-Trace or Flasher remotely - anywhere in the world

    Mar. 2019 | 4:35 min
    J-Link Remote Server — Intro

    SEGGER J-Link Pro: Performance analysis on RISC-V

    Jan. 2022 | 4:02 min
    J-Link — Performance analysis

    An introduction to Cortex-M faults and how SEGGER's Ozone debugger can help

    Aug. 2020 | 5:22 min
    J-Link & Ozone — Intro Cortex-M Faults

    Analyzing Cortex-M faults using SEGGER's Ozone debugger

    Aug. 2020 | 7:30 min
    J-Link & Ozone — Cortex-M Faults analysis

    SEGGER BBC micro:bit J-Link upgrade: Step-by-step instructions

    Aug. 2016 | 1:33 min
    BBC micro:bit J-Link Upgrade — Intro

       View more...

    Technical

    General
    Supported OSMicrosoft Windows (x86/x64), Linux (x86/x64/Arm), macOS (x86/Apple Silicon)
    Electromagnetic compatibility (EMC)EN 55024, EN 55032
    Operating temperature+5°C ... +60°C
    Storage temperature-20°C ... +65 °C
    Relative humidity (non-condensing)Max. 90% rH
    Mechanical
    Size (without cables)100mm x 53mm x 27mm
    Weight (without cables)73g
    Available Interfaces
    USB interfaceUSB 2.0, (Hi-Speed)
    Target interfaceJTAG/SWD 20-pin
    JTAG/SWD Interface, Electrical
    Target interface voltage (VIF)1.2V ... 5V
    Current drawn from target voltage sense pin (VTRef)< 25µA
    Target supply voltage5V (derived from USB voltage)
    Target supply currentMax. 300mA
    Reset typeOpen drain with 100 Ohms series resistor. Can be pulled low or tristated
    Reset low level output voltageVOL <= 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 kOhmVOL <= 20% of VIF
    HIGH level output voltage (VOH) with a load of 10 kOhmVOH >= 80% of VIF
    For 3.6 <= VIF <= 5V
    LOW level output voltage (VOL) with a load of 10 kOhmVOL <= 20% of VIF
    HIGH level output voltage (VOH) with a load of 10 kOhmVOH >= 80% of VIF
    JTAG/SWD Interface, Timing
    Target interface speedMax. 50 MHz
    SWO sampling frequencyMax. 100 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
    Analog power measurement interface
    Sampling frequency200 kHz
    Resolution50 uA

    Package content

    SEGGER J-Link Ultra+
    J-Link ULTRA+
    J-Link ULTRA+: 20-pin, 0.1" target ribbon cable
    20-pin, 0.1" target ribbon cable
    J-Link ULTRA+: USB cable black
    USB cable

    FAQ

    Q: Can I use J-Flash with J-Link ULTRA+?

    A:  Yes. J-Link ULTRA+ comes with a license for J-Flash preinstalled on the probe itself. No license setup necessary, simply plug in J-Link ULTRA+ and start using J-Flash.

    Q: What is the advantage of J-Link versus simple probes such as FTDI-based systems?

    A:  J-Link has numerous advantages: the actual J-Link software supplied by SEGGER (which enables use with common IDEs), the availability of Unlimited Flash Breakpoints for the debugging of software which runs in the flash of microcontrollers, it’s high speed and it’s simple, fast download into flash memory.

    In contrast to most simple probes, J-Link supports adaptive clocking as well as SWD and SWO. It also functions more stably, since it is not just a dump USB to JTAG converter. Instead, it uses the intelligence of the built-in CPU which provides more robust communication. This is especially so in situations where the target CPU runs at low clock speeds.

    Q: May I work with more than one J-Link at the same time, on the same machine?

    A:  Yes, you can connect an unlimited number of J-Links to your PC. No special configuration is required; each J-Link is registered with its unique serial number on the PC. This enables you to have multiple J-Links connected at once.

    Q: I have multiple Arm cores in my JTAG chain. How can I debug them (simultaneously) with J-Link?

    A:  That's simple: Two or more debuggers can use the same J-Link simultaneously. Multi-core debugging requires multiple debuggers or multiple instances of the same debugger. You need to tell your debugger which device in the scan chain you want to debug. Additional special settings are not required.

    Q: Does J-Link support the Embedded Trace Buffer (ETB)?

    A:  Yes. J-Link supports ETB on Cortex-M3/M4/M7 and Cortex-A/R (if implemented by target device).

    Q: Does J-Link support the  Micro Trace Buffer (MTB)?

    A:  Yes.

    Q: Does J-Link support the Embedded Trace Macrocell (ETM)?

    A:  No. ETM requires another connection to the ARM chip and a CPU with built-in ETM. ETM is supported by the J-Trace product family.


    Latest news

    2025
    Jul.09
    J-Link
    J-Link devices alongside Renesas RA8P1

    SEGGER delivers J-Link and Flasher support for Renesas Electronics's RA8P1

    SEGGER's J-Link series of debug probes and Flasher programmers are now compatible with Renesas Electronics's high-performance group of RA8P1 microcontrollers (MCUs). The MCUs are powered by the Arm® Cortex®-M85 (CM85) processor with a Helium™ M-Profile Vector Extension and Ethos™-U55 neural processing unit.

    [Read more...]

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