https://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/<p style="display:none;">blank</p>en-USTelligent Community 13https://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659455/trf7970a-rx-pin-voltage-level-issue/6410986Thu, 09 Jul 2026 13:52:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:bed005e1-72bd-4f4e-b80e-4fc192f2baa0Rizwan MurjiHi, I apologies for the late reply. Please note that this family of devices have limited support but I will do my best to address you issue. It looks like you have 2 issues: The datasheet describes that in direct mode 0, when the RX pin does not emit waves, it is at a low level. However, when I tested that it does not emit waves, the RX pin is at a high level. Is there any difference between the two? Yes, there is an important functional and operational difference between the two behaviors. In Direct Mode 0 , the digital pin designated to output the raw subcarrier data ( I/O_6 / MISO ) reflects the state of the raw analog digitizer loop. Seeing this pin sit high instead of low during idle states when no tag is emitting waves is an indicator of specific hardware or firmware states. The Key Differences 1. Noise Floor and Gain Saturation Datasheet Low State : The datasheet assumes an ideal, quiet RF environment. When no tag is present and the RF field is active, there should be no subcarrier modulation. The digitizer sees a flat baseline and outputs a stable low logic level . Observed High State : If your pin is sitting continuously high, the internal receiver gain stages are likely saturated, or the system is capturing environmental RF noise or transmitter phase noise. The internal digitizer interprets this continuous baseline offset or noise as a high logic state. 2. Receiver Glitch / Lock-Up State The Cause : The TRF7970A internal analog-to-digital digitizer has an auto-zero or baseline tracking loop. If the transmitter turns on or changes modes abruptly without the receiver being correctly reset, the receiver&#39;s threshold detector can lock up in a logic high state. The Impact : While stuck high, the chip cannot cleanly toggle to represent incoming subcarrier edges from a tag. The host microcontroller will fail to detect the start-of-frame edges because the baseline has shifted. 3. Missing Band-Pass Filter / Sync Settings The Cause : In Direct Mode 0, you bypass the framing hardware, but the internal analog filter chain is still active. If the band-pass filter ( Register 0x0A ) or the modulator control settings are not fully matched to your expected subcarrier frequency (e.g., 424 kHz or 848 kHz), the receiver won&#39;t track the zero-signal baseline correctly, resting at a high rail. How to Fix It Clear the Receiver : Before waiting for data in Direct Mode 0, always issue a Reset RX Gain (0x1A) or Soft Init (0x03) direct command to clear the digitizer loops and force the baseline back to low. Check the Match Network : Check the peak-to-peak AC voltage on the physical RX_IN1 and RX_IN2 pins. If it is too close to (or exceeding) 3Vpp , the transmitter is leaking directly into the receiver, blinding it and forcing the digital output high. Use Direct Mode 1 : If you are using Direct Mode 0 to decode a non-standard or proprietary protocol, consider migrating to Direct Mode 1 or Special Direct Mode . These modes provide an extracted clock alongside the data stream, making the idle state of the pin less susceptible to resting-state high/low logic errors. For the ESD issue: The 20us low pulse is actively emitted by the internal digital control and auto-zero loops of the TRF7970A Analog Front End (AFE). It is a direct reaction to the electrostatic discharge (ESD) event blinding the receiver. Because the system is running in Direct Mode 0 , the framing logic is entirely bypassed. The I/O_6 pin simply reflects the real-time digitized output of the raw receiver chain. Why the 20us Low Pulse Occurs: ESD Induces Receiver Saturation : The electrostatic discharge induces a severe common-mode voltage spike on the RX_IN1 and RX_IN2 pins. This transient energy saturates the internal analog input amplifiers. The 10us Internal Delay : The internal analog filters and gain stages take approximately \(10\ \mu\text{s}\) to desaturate and stabilize after the sudden ESD spike clears. The 20us Pulse (Active Baseline Clamping) : To recover from saturation, the TRF7970A activates its internal baseline tracking and auto-zero loop (clamping circuits). This active discharge process pulls the internal comparator down, forcing I/O_6 to a logic low for roughly 20us . Once the clamping phase completes, the digitizer releases, but because the baseline shifted during the shock, it registers as a permanent high state, flooding the MCU with 0xFF data blocks. To resolve the issue Force a &quot;Reset RX Gain&quot; Command When an ESD spike hits, the baseline recovery loop often overcompensates, latching I/O_6 high permanently. Have the MCU detect if I/O_6 remains high without toggling for more than 50us. If it latches high, immediately send the Reset RX Gain (0x1A) direct command followed by a Soft Init (0x03) command over SPI. This resets the internal thresholds and instantly forces I/O_6 back to its proper resting state. I hope this helps. Thanks, Rizhttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1661815/cc2591-2-2-ghz-peak-observed-in-emi-testingTue, 07 Jul 2026 07:56:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:a0b0e1c0-c3d1-4418-b8c9-0b87ee8518fcAkhil AithalPart Number: CC2591 Other Parts Discussed in Thread: CC2520 Hello, we are using a CC2520 zigbee transmitter in combination with a CC2591 range extender for our product. While carrying out the EMI testing, we find that there exists a 2.2GHz peak along with our intended 2.4GHz signal. The magnitude of the signal is comparable to the 2.4GHz signal. We are using a test software to transmit every 10-100ms and we are able to set the channel and transmit power. What we observe is that the channel and transmit power of our target signal at 2.4GHz is behaving as per our setting, but the unintended signal at 2.2GHz remains unchanged in its frequency as well as power for any setting. I am looking to find the root cause and potential solutions for this. It would be very helpful if you could support. Thank you. Regards, AkhilCC2520CC2591Test &amp; Measurementhttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1661168/cc2340r5-openocd-and-cc2340r5-launchpad/6405539Mon, 06 Jul 2026 12:46:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:0cd47fe3-004e-4e5a-9170-a647fccf69d3Andy RutterThank you. I was trying to use the download from https://software-dl.ti.com/ccs/esd/vscode/ti-embedded-debug/ti-openocd.html but that doesn&#39;t have the latest board files.https://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659455/trf7970a-rx-pin-voltage-level-issue/6405317Mon, 06 Jul 2026 08:59:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:00cf6453-9d5b-42fa-8c1e-568feb682fa6user5883945customer tested the EVM board and encountered the same issue.https://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1661168/cc2340r5-openocd-and-cc2340r5-launchpad/6405280Mon, 06 Jul 2026 08:33:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:546798c7-bc2f-4143-bc8d-a94c258d9504LeaHi Andy ! For the CC2340R5, you should use the https://github.com/TexasInstruments/ti-openocd/blob/ti-release/tcl/board/ti_lp_em_cc2340r5.cfg file. This file is only usable in the ti-openocd repository, not the official upstream openocd repository. Kind regards, Leahttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1661168/cc2340r5-openocd-and-cc2340r5-launchpadFri, 03 Jul 2026 21:56:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:a4f2dbba-9ad5-4b11-be76-134c52d86c9fAndy RutterPart Number: CC2340R5 Which openocd board .cfg file should I use for the cc2340r5 launchpad development board? -- AndyPortable ElectronicsCC2340R5https://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659455/trf7970a-rx-pin-voltage-level-issue/6404362Fri, 03 Jul 2026 09:23:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:0774d062-35eb-410c-8221-d1b7c4a84218user5883945Hello, Is there any update?https://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659455/trf7970a-rx-pin-voltage-level-issue/6401296Wed, 01 Jul 2026 12:32:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:4b5f0643-d117-448e-b6e4-7d153698c696user5883945Dear, Today I went to the customer&#39;s laboratory to investigate the problem on-site. At the moment of static electricity, there will be a spike with a short interval when measuring the waveform of the I/O6 pin. Afterwards, delay by about 10us and output a low pulse of about 20us. The following adjustments have been made: 1. The bypass capacitor of power VIN (pin2) has increased from 2.2uF to 47uF; 2. I/O6 has added an RC low-pass filtering circuit; The above adjustments have not improved. Based on this, it is suspected that after the low pulse was generated, the MCU judged it as the starting signal of RX, which remained at a high level thereafter. The signals collected by the MCU were all FFF garbled information. Is this low pulse of around 20us actively emitted from within the IC and how can it be eliminated? Customers can receive spikes caused by electrostatic coupling, but cannot receive garbled codes.https://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659945/cc2662rq1-bcu-evm-available-to-purchase/6400346Tue, 30 Jun 2026 19:56:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:c4da49a9-2b5f-4a76-8ce7-be101101b08bEvan WHi Caitlyn, Yes, it&#39;s available for purchase but does require an NDA with TI. You can request approval to purchase here. CC2662RQ1-BCU-EVM Evaluation board | TI.comhttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659945/cc2662rq1-bcu-evm-available-to-purchaseTue, 30 Jun 2026 19:38:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:2089a6ff-f6ab-4716-9e70-2a89825331bcCaitlyn CavanaghPart Number: CC2662RQ1-BCU-EVM Hello, is the CC2662RQ1-BCU-EVM available to purchase? If not, can you recommend a similar product that is available?CC2662RQ1-BCU-EVMhttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1650265/cc8530-cc8530-cc2592-range-issue/6399908Tue, 30 Jun 2026 14:51:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:09dba8eb-1358-409b-bf25-b6dc8849dd5eRyan Brown1It appears that the tests believe to have passed. Either the RF front end is not set up properly to transmit, the spectrum analyzer is not tuned to the correct frequency, or the TX at each channel is too short to be observed with current spectrum analyzer settings. Does your RX test RSSI noise floor change when running the TX test specifically? Note that you will have to align with a channels frequency being used in the TX test. Regards, Ryanhttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1650265/cc8530-cc8530-cc2592-range-issue/6399488Tue, 30 Jun 2026 08:57:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:13c0b2de-0d8b-4609-8c05-9956f5f34d6dSrilakshmi HHi Ryan, Please find the Observation in the below document, e2e.ti.com/.../RF_5F00_CC8530_5F00_CC2592_5F00_Range_5F00_issue_5F00_30062026.docx Regards, Srilakshmihttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659455/trf7970a-rx-pin-voltage-level-issue/6399760Tue, 30 Jun 2026 07:52:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:79540e97-63ec-4fdb-b0da-96b7177a34abuser5883945Part Number: TRF7970A Dear, During the ESD test, the MISO output level instantly pull down, and normal communication was restored afterwards. Testing method: The ESD grab did not make any contact with the product casing, only discharged to the ground on the nearby testing platform. After replacing the passive crystal oscillator with an active crystal oscillator, the waveform of the crystal oscillator became much more stable, but the MISO was still pulled down.Industrial AutomationTRF7970Ahttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659455/trf7970a-rx-pin-voltage-level-issue/6399407Tue, 30 Jun 2026 07:39:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:4ea2e9c7-f266-4433-a003-54f8d78b00bauser5883945Dear, In DM0 mode, when RX is idle with no data, I/O6 outputs a high level. And Figure 6-32 in the datasheet shows a low level. Is this reasonable?https://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659455/trf7970a-rx-pin-voltage-level-issueMon, 29 Jun 2026 14:10:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:eb6baf86-229b-4bb8-a889-285ab8737d50user5883945Part Number: TRF7970A Dears, The datasheet describes that in direct mode 0, when the RX pin does not emit waves, it is at a low level. However, when I tested that it does not emit waves, the RX pin is at a high level. Is there any difference between the two?Industrial AutomationTRF7970Ahttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659004/cc8520-input-voltage-clarification/6396716Fri, 26 Jun 2026 14:23:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:570c1dba-47ce-4f6f-bee8-40278108753aLeaHi ! This sounds like a duplicate of CC8520: 1.8V logic compatibility? You can contribute to the other thread if you wish. Kind regards, Leahttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1659004/cc8520-input-voltage-clarificationFri, 26 Jun 2026 14:11:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:69967ddd-e935-4f3d-8ca4-881190556d98Alex SeglerPart Number: CC8520 Hello team - can you tell me if there is a configuration of CC8520 within your recommendations that is compatible with 1.8V logic? We are trying to avoid a level shifter and the datasheet does not provide logic voltage thresholds. Assuming V(high)=0.7Vcc, I think it would be valid to run CC8520 at Vcc=2.0V and that should allow it to be compatible with logic levels. Thanks!cc8520Applianceshttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1650265/cc8530-cc8530-cc2592-range-issue/6396665Fri, 26 Jun 2026 13:34:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:1be0df6a-fb30-42bc-acd6-648d31dcefa5Ryan Brown1After loading the production test image, are you following the Production Test instructions to run the test? Have you ensured that you&#39;ve correctly connected the radio output to the Spectrum Analyzer and that this tool is tuned to the correct frequency? Regards, Ryanhttps://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1650265/cc8530-cc8530-cc2592-range-issue/6396003Fri, 26 Jun 2026 02:36:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:62df50b9-a8e2-4b61-b651-0199a6bfd425Srilakshmi HHi Ryan, We have reviewed the E2E forum guidance and programmed the device with the TX-only production test configuration ( prod_test_simplerf_tx.ppwptc ) . According to the documentation, this test does not require a TESTER and the result can be verified using either a spectrum analyzer or the RXTX panel. However, after flashing the configuration, we are unable to observe any RF transmission or measure the transmit power on the spectrum analyzer. We would appreciate your guidance on further debug steps.https://e2e.ti.com/support/wireless-connectivity/other-wireless-group/other-wireless/f/other-wireless-technologies-forum/1650265/cc8530-cc8530-cc2592-range-issue/6390298Mon, 22 Jun 2026 12:11:00 GMTcb01d8b2-d089-468d-babb-77d1d8683490:b0e242b1-2c5a-4c98-bfff-8e51f5e95b11Ryan Brown1Hello Vinay, Here are two E2E threads with instructions on this topic: CC8530: Using PurePath Wireless Commander Error occurred. Please solve the problem. CC8520: CC8520 + CC2590 wireless outdoor distance issue Regards, Ryan