RF Built-in Self Test of a Wireless Transmitter

RF frequency synthesizers and transmitters for wireless system-on-chips have recently migrated to low-cost deep-submicrometer CMOS processes that facilitate all-digital implementations. In addition to all the benefits of lower power, lower silicon cost, reduced board area, and improved performance that the scaled CMOS integration entails, the testing costs for RF performance and wireless standard compliance could also be drastically reduced. In this brief, we propose a built-in self test (BIST) method, which is based on the premise that the internal frequency synthesizer and transmitter signals are in digital format allowing for digital signal processing to ascertain the RF performance without external test equipment. With the RF BIST capability, millions of SoCs can be calibrated and tested in a production environment using a low cost digital tester while benefiting from increased test coverage and reduced test time and cost. The presented techniques have been successfully implemented in two generations of commercial digital RF processors: 130-nm Bluetooth and 90-nm GSM single-chip radios