Analog Devices, Inc. has announced the ADF4157, a fractional-N PLL synthesizer. Optimized for phase noise and tuning resolution, the new device is well suited for use in satellite communications, private mobile radios (PMR), instrumentation and wireless base station equipment, including those that support GSM, PCS, DCS, WiMAX, CDMA and W-CDMA networks. Design and simulation software is available as a free download (http://www.analog.com/adisimpll).
The ADF4157 operates up to 6-GHz using a power supply ranging from +2.7 to +3.3 VDC. The device can be powered down when not in use, resulting in overall system current reduction from 23 mA to 0.01 mA. The ADF4157 consists of a low-noise digital phase-frequency detector (PFD), a precision high-voltage charge pump, a programmable reference divider, programmable charge pump currents and a 25-bit fixed-modulus fractional divider. Additionally, the RF output phase is programmable for applications that require a particular phase relationship between the output and the reference. A three-wire interface controls all of the on-chip registers. The ADF4157 also features separate VP for extended VCO tuning voltage and a digital lock-detect function.
The ADF4157 is fully pin-compatible with the ADF411x, ADF410x and ADF415x PLL synthesizers from Analog Devices.
The ADF4157 is available in two package options, a 20-lead LFCSP (lead-frame chip-scale package) and a 16-lead TSSOP (thin-shrink small-outline package), and is priced at $3.21 per unit in quantities of 1,000.