Nordic nRF51/nRF52 hardware development process description

Nordic nRF51 series includes nRF51822/nRF51422/nRF51802 and other chips, nRF52 series includes nRF52832/nRF52840/nRF52810 and other chips, you can develop nRF51/52 hardware circuit according to the following process (nRF51/52 software development process, please refer to the next article)

1. Step 1: Selection evaluation. This is mainly achieved by consulting the nRF51/52 spec. There is only one spec for nRF52. The spec contains an overview of the functions of the chip peripheral modules, electrical characteristic parameters, application reference circuits, packaging and ordering information. The front of each peripheral module chapter of the nRF52 spec is an overview of its functions, and the last section is Electrical characteristic parameter display. The nRF51 reference manual and spec are separate. The reference manual mainly describes the function and principle of each peripheral module, and the spec is used to describe the electrical characteristic parameters, application reference circuit, packaging and ordering information.
   • nRF51参考手册（reference manual）：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf51%2Fdita%2Fnrf51%2Fpdflinks%2Fref_manual.html&cp=3_2。
   • nRF51822 spec (other nRF51 spec links are similar, I believe you can find it yourself): http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf51%2Fdita%2Fnrf51%2Fpdflinks%2F51822_ps .html&cp=3_4_0
   • nRF52832 spec：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Fchips%2Fnrf52832_ps.html&cp=2_1_0
   • nRF52840 spec：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Fchips%2Fnrf52840_ps.html&cp=2_0_0
   • nRF52810 spec：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Fchips%2Fnrf52810_ps.html&cp=2_2_0
2. Step 2: Apply for the nRF51/52 development board (Development Kit, DK). Most of Nordic's examples are developed and tested on the nRF51/52 development board. Having the nRF51/52 development board on hand will greatly facilitate the development of software engineers. The nRF51/52 development board can also be used as a reference board to troubleshoot user board problems. During production testing, the nRF51/52 development board can also be used as a gold sample to test whether the RF performance of the user board is qualified. Finally, the nRF51/52 development board also comes with a genuine Jlink chip, which means that the nRF51/52 development board itself is a Jlink writer, which can not only be used to program the nRF51/52 chip on the board, but also can be used to program Jlink chips on other user boards. A genuine Jlink programmer is priced at about 1000 RMB on Taobao, while the official price of Nordic nRF51/52 development board is only 39 US dollars, which can be described as "the price is kind and touching." (PS: If you get the Nordic nRF51/52 official DK, you will find that the Nordic DK is the best in the industry, no one!)
   • The nRF51 development board number is PCA10028, and the DK purchase link is: http://www.nordicsemi.com/eng/Buy-Online?search_token=nRF51-DK
   • The nRF52832/nRF52810 development board number is PCA10040, and the DK purchase link is: http://www.nordicsemi.com/eng/Buy-Online?search_token=nRF52-DK
   • The nRF52840 development board number is PCA10059 or PCA10056 (engineering version), and the DK purchase link is: http://www.nordicsemi.com/eng/Buy-Online?search_token=nRF52840-PDK
3. Step 3: Circuit Design. It is recommended to design your own circuit according to the nRF51/52 reference circuit. Of course, you can also design your own circuit according to the nRF51/52 DK (development board). These two reference circuits are equivalent, and both provide a complete BOM table, schematic diagram and layout for your reference.
   • nRF51 reference circuit: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf51%2Fdita%2Fnrf51%2Fpdflinks%2Fref_layout.html&cp=3_6
   • nRF52 reference circuit: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Fpdflinks%2Fref_layout.html&cp=2_5
   • nRF51 DK circuit diagram: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf51%2Fdita%2Fnrf51%2Fnrf51_development.html&cp=3_1 (Note: There is also nRF51 dongle in this link Circuit diagram, nRF51 dongle uses a very small snake antenna, if your board space is limited, you can also refer to nRF51 dongle for wiring)
   • nRF52832/52810 DK circuit diagram: https://www.nordicsemi.com/eng/nordic/download_resource/50980/7/99707889/93935
   • nRF52840 DK circuit diagram: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Fdevelopment%2Fnrf52840_pdk%2Fkit_download_content.html&cp=2_0_3_2_1
   • Nordic also provides some circuit design notes for your reference: https://devzone.nordicsemi.com/tutorials/b/hardware-and-layout/posts/general-pcb-design-guidelines-for-nrf51-series
4. Step 4: Bluetooth RF performance debugging. Nordic has corresponding guidance documents for the three most critical factors affecting Bluetooth RF performance: matching circuit debugging, antenna design debugging and crystal oscillator selection.
   1. Matching circuit debugging: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.whitepapers%2Fdita%2Fwhitepapers%2Fpdflinks%2Fnwp_013.html
   2. Antenna Design: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.whitepapers%2Fdita%2Fwhitepapers%2Fpdflinks%2Fnwp_017.html
   3. Crystal selection: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.whitepapers%2Fdita%2Fwhitepapers%2Fpdflinks%2Fnwp_015.html&cp=11_11
5. Step 5: Circuit diagram and layout review. Nordic or its agents provide schematics and layout review services for free. We can submit schematics and layouts to Nordic Devzone for review. Generally, Nordic engineers can reply within 1 to 2 working days. For the circuit diagram submission process, please refer to the article (section 3: Nordic Devzone): Nordic official website/Infocenter/Devzone/Github introduction
6. Step 6: Play the board. Nordic also has corresponding guidance documents on how to mount. At present, Nordic chips only have three packages: QFN, WLCSP and aQFN. The relevant patch instructions are as follows:
   • QFN：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.appnotes%2Fdita%2Fappnotes%2Fpdflinks%2Fnan_400-08.html
   • WLCSP：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.appnotes%2Fdita%2Fappnotes%2Fpdflinks%2Fnan_38.html
   • aQFN：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.appnotes%2Fdita%2Fappnotes%2Fnan40%2Fnan40_intro.html&cp=10_0
7. Step 7: RF Test. If you have dedicated BLE test equipment, you can test the RF performance of the board yourself. It doesn't matter if you don't have a BLE test device, Nordic or its agents provide BLE test services for free. Just send the board to Nordic dealer labs, or Nordic labs, or third-party labs like R&S labs, and they can help you with BLE performance and compliance testing. You can make secondary corrections to the board according to the experimental test results.
   • RF DTM test device firmware and test instructions: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.appnotes%2Fdita%2Fappnotes%2Fpdflinks%2Fnan_34.html
   • General radio test firmware and test instructions: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.sdk5.v15.0.0%2Fnrf_radio_test_example.html&cp=4_0_0_4_5_29
8. Step 8: Power consumption test. The power consumption test can refer to the following link:
   • Power consumption test introduction: https://devzone.nordicsemi.com/tutorials/b/hardware-and-layout/posts/current-measurement-guide-introduction
   • Power Consumption Test Guide: https://devzone.nordicsemi.com/tutorials/b/hardware-and-layout/posts/nrf51-current-consumption-guide
   • BLE theoretical power consumption calculation tool: https://devzone.nordicsemi.com/power/
9. Step 9: Errata Self-Check. The contents of the errata are generally about the precautions for software development, but it is not excluded that some items are also related to the hardware design, so it is recommended to check the errata before the official version to prevent stepping on the "pit"
   • nRF51822 Errata (PAN) (other nRF51 series links are similar, I believe you can find it yourself): http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf51%2Fdita%2Fnrf51 %2Fpdflinks%2FnRF51822_pan.html&cp=3_4_1
   • nRF52832勘误表（Errata）：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Ferrata.html&cp=2_1_1
   • nRF52840勘误表（Errata）：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Ferrata52840.html&cp=2_0_1
   • nRF52810勘误表（Errata）：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Ferrata52810.html&cp=2_2_1
10. Step 10 (Optional): Authentication. According to product needs, you can do BQB certification, SRRC certification, FCC certification, ETSI certification, environmental testing, etc. Like BQB certification, Nordic products themselves have obtained the corresponding QDID, and your certification can reuse Nordic QDID.
    • Nordic QDID query. Enter the URL: https://launchstudio.bluetooth.com/Listings/Search , and enter "Nordic Semiconductor" in the search box to search for all Nordic QDIDs.
    • Environmental Report: https://www.nordicsemi.com/eng/About-us/Corporate-Social-Responsibility/Environment
    • nRF52 Material composition reports (MCR) and hazardous substance reports (HSR) 报告：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf52%2Fdita%2Fnrf52%2Fnrf52_env_reports.html&cp=2_7
    • nRF51Material composition reports (MCR) and hazardous substance reports (HSR)报告 ：http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.nrf51%2Fdita%2Fnrf51%2Fpdflinks%2FnRF51_env_reports.html&cp=3_8
    • For BT/ANT/FCC/ETSI certification, please refer to Nordic documentation: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.gs%2Fdita%2Fgs%2Fcertifying.html&cp=1_5
    • Test firmware code (same as Step 7: RF Test Firmware Code) . Nordic provides two sets of RF test firmware, one is DTM test code, which conforms to the Bluetooth DTM standard, located in the directory: SDK installation directory\examples\dtm\direct_test_mode, please refer to: http://infocenter.nordicsemi.com/index for details .jsp?topic=%2Fcom.nordic.infocenter.sdk5.v12.3.0%2Fble_sdk_app_dtm_serial.html&cp=4_0_2_4_4 ; a set of radio test code is used to directly test the physical performance of each RF channel, such as frequency offset, etc., located in the directory: SDK installation directory\examples\peripheral\radio_test, please refer to: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.sdk5.v12.3.0%2Fnrf_radio_test_example.html&cp=4_0_2_4_5_25 . Generally speaking, when testing the packet loss rate, it is recommended to use DTM test codes, such as BQB certification and production test; if you only need to simply test the carrier frequency and frequency offset of the RF channel, it is recommended to use the radio_test code, such as SRRC certification.
11. Step 11: Build a mass production programming environment. Nordic does not provide mass production programmers, but Nordic agents or Taobao have relevant mass production programming tools. In fact, Jlink programmers that support SWD interface can be used to program Nordic products. Although Nordic does not provide a mass production programmer, Nordic provides a mass production programming DLL library: nrfjprog, nrfjprog can be executed directly in the Windows command line tool, or it can be executed using a Python script, or it can be developed by users themselves. Program the software to call. To write your own Jlink programming software, please refer to the white paper: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.whitepapers%2Fdita%2Fwhitepapers%2Fnwp_027%2Fintro.html
12. Step 12: Set up a production test environment. Generally speaking, there are two production testing methods: one is to use expensive professional equipment for production testing, such as Litepoint, Anritsu, etc., the other is to use Nordic's nRF51/52 DK as the gold sample to test the DUT, which is low-cost and effective. . For details, please refer to Nordic application note: http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.appnotes%2Fdita%2Fappnotes%2Fpdflinks%2Fnan_34.html&cp=10_3 (Note: used for production testing The firmware is still the aforementioned DTM firmware!)
13. Step 13: Small batch trial production. Focus on product consistency, yield and throughput.
14. Step 14: Mass Production. Product launch!