In April 2021 we started to subject our KRM-4ZUxxDR modules to an extensive temperature test on a KRC-4700 test carrier, extended outside of our temperature specification of 0 °C to 70 °C for a commercial grade module, to underline our high-quality standards and our reliability.

For this function test, we have developed a test setup in which we put the KRM-4ZUxxDR through its paces between -60 °C and +80 °C in our climatic chamber. The junction temperature of the Xilinx Zynq-RFSoC component is also monitored to ensure that this specification for Tj does not exceed 100 °C.

In the test, a power cycle test is started in 20 °C steps for all temperature settings. After switching on, the following test procedures run: IBERT, memory and Linux test.

The IBERT (Integrated Bit Error Ratio Tester) tests the gigabit transceiver via QSFP loop-back at 100 Gbps (4 lanes at 25 Gbps). The memory test loads a MIG (Memory Interface Generator) sample design, calibrates and tests the memory controller and exports the eye width as the result. In the Linux test, the SD card is booted and a “rf analyzer” sample design is started. It is recognized whether the Ethernet connection is established, USB, QSFP and eMMC are detected and the clock board PLLs are “LOCKED”. In a Linux endurance test, the running system is externally supplied with data packets via SSH, these are read back and checked whether packet losses have occurred.

The result has shown that all test results between -60 °C and + 80 °C are perfect and faultless … and this is even beyond the temperature spec limits. We would be happy to share these test results with you. If you are interested, please contact us at