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GENERAL DESCRIPTION The ADF4110 family of frequency synthesizers can be used to implement local oscillators in the upconversion and downconversion sections of wireless receivers and transmitters. They consist of a low noise digital PFD (phase frequency detector), a precision charge pump, a programmable reference divider, programmable A and B counters, and a dual-modulus prescaler (P/P + 1). The A (6-bit) and B (13-bit) counters, in conjunction with the dual-modulus prescaler (P/P + 1), implement an N divider (N = BP + A). In addition, the 14-bit reference counter (R counter) allows selectable REFIN frequencies at the PFD input. A complete phase-locked loop (PLL) can be implemented if the synthesizer is used with an external loop filter and voltage controlled oscillator (VCO). FEATURES ADF4110: 550 MHz; ADF4111: 1.2 GHz; ADF4112: 3.0 GHz; ADF4113: 4.0 GHz 2.7 V to 5.5 V power supply Separate charge pump supply (VP) allows extended tuning voltage in 3 V systems Programmable dual-modulus prescaler 8/9, 16/17, 32/33, 64/65 Programmable charge pump currents Programmable antibacklash pulse width 3-wire serial interface Analog and digital lock detect Hardware and software power-down mode APPLICATIONS Base stations for wireless radio (GSM, PCS, DCS, CDMA, WCDMA) Wireless handsets (GSM, PCS, DCS, CDMA, WCDMA) Wireless LANS Communications test equipment CATV equipment
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