This document provides information about the silicon anomalies of the ADF7021 narrow-band transceiver IC and includes workarounds for these issues. One known issue is the inability to access the sync word detect signal on the SWD pin in 4FSK mode.
The Silicon Anomaly Sheet for the ADF7021 narrow‑band transceiver documents all known silicon bugs, anomalies, and recommended workarounds. It targets Silicon Revision 4 (readback code 0x2104) and is intended to help designers maintain compatibility with existing software and hardware.
Key issues covered include the inability to access the Sync Word Detect (SWD) pin in 4FSK mode, limitations of IF filter fine calibration for crystal frequencies above 16.7 MHz, and detailed register programming sequences to implement workarounds. The sheet also provides guidance on when coarse calibration is sufficient and how to monitor calibration completion signals.
| Silicon revision readback code | 0x2104 |
|---|---|
| IF filter bandwidth options | 25 kHz, 18.75 kHz, 12.5 kHz |
| IF filter center frequency | 100 kHz |
| Maximum crystal/TCXO frequency for fine calibration | 16.7 MHz |
No, the SWD pin is automatically muxed to the test DAC output in 4FSK mode, preventing access to the sync word detect signal.
The ADF7021 offers selectable IF filter bandwidths of 25 kHz, 18.75 kHz, and 12.5 kHz.
Use a crystal/TCXO below 16.7 MHz, or follow the register programming sequence described in the sheet; for crystals above 21.33 MHz only coarse calibration is possible.