Analog Devices Introduces 8-GHz PLL Synthesizer

Norwood, MA -- Analog Devices, Inc. announced what the company claims is the industry's first 8-GHz phase-locked loop (PLL) synthesizer. The new ADF4108 is targeted at high-frequency wireless systems, such as those used for broadband wireless access, satellite communications, instrumentation, wireless LANs and base stations for wireless radio.

"ADI's RF and wireless engineering efforts are built upon an allegiance to innovation, quality and solving the signal processing challenges of its customers," said Christian Kermarrec, vice president, RF and wireless systems, Analog Devices, Inc. "The ADF4108 is the latest example of how we continue to develop products that ease wireless system design while maintaining high performance."

The new ADF4108 will be showcased at this year's IEEE MTT-S International Microwave Symposium taking place June 11-16 in San Francisco, Calif.

The ADF4108 deepens Analog Devices' broad range of RF ICs and technologies, which includes direct digital synthesizers; PLL synthesizers; detectors and logarithmic amplifiers; fixed and variable gain amplifiers; mixers, modulators, and demodulators; integrated IF amplifiers; RF transmitters and transceivers, and the Othello family of single-chip transceivers for cellular terminals. Analog Devices also offers ADIsimPLL, a PLL circuit design and evaluation tool, and ADIismLINK, a development tool for users of Analog Devices' ISM band transceivers for short range wireless connectivity.

Operating at 8 GHz, the ADF4108 can be used to implement local oscillators in the up-conversion and down-conversion sections of wireless receivers and transmitters. It consists of a low-noise digital PFD (phase frequency detector), a precision charge pump, a programmable reference divider, programmable A (6-bit) and B (13-bit) counters, and a dual-modulus prescaler (P/P + 1). The A and B counters, in conjunction with the dual-modulus prescaler, implement an N divider (N = BP+A). In addition, the 14-bit reference counter (R counter) allows selectable REFIN frequencies at the PFD input. The ADF4108 has a power supply range of 3.2-3.6V and a separate charge pump supply (VP) allows extended tuning voltage in 3.3V systems. A complete PLL can be implemented if the synthesizer is used with an external loop filter and voltage controlled oscillator.

SOURCE: Analog Devices, Inc.