Features and Benefits
- 2.0 GHz/1.1 GHz
- 2.7 V to 5.5 V power supply
- Selectable charge pump supply (VP) allows extended tuning voltage in 3 V systems
- Selectable charge pump currents
- On-chip oscillator circuit
- Selectable dual modulus prescaler
- RF2: 32/33 or 64/65
- RF1: 32/33 or 64/65
- 3-wire serial interface
- Power-down mode
The ADF420x family of dual frequency synthesizers are used to implement local oscillators in the upconversion and downconversion sections of wireless receivers and transmitters. Each synthesizer consists of a low noise, digital, phase frequency detector (PFD); 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 (11-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. The on-chip oscillator circuitry allows the reference input to be derived from crystal oscillators.
A complete phase-locked loop (PLL) can be implemented if the synthesizers are used with an external loop filter and voltage controlled oscillators (VCOs).
Control of all the on-chip registers is via a simple 3-wire interface. The devices operate with a power supply ranging from 2.7 V to 5.5 V and can be powered down when not in use.
- Wireless handsets (GSM, PCS, DCS, CDMA, WCDMA)
- Base stations for wireless radio (GSM, PCS, DCS, CDMA, WCDMA)
- Wireless LANS Communications test equipment
- CATV equipment
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Tools & Simulations
ADIsimPLL enables the rapid and reliable evaluation of new high performance PLL products from ADI. It is the most comprehensive PLL Synthesizer design and simulation tool available today. Simulations performed include all key non-linear effects that are significant in affecting PLL performance. ADIsimPLL removes at least one iteration from the design process, thereby speeding the design- to-market.
ADIsimRF is an easy-to-use RF signal chain calculator. Cascaded gain, noise, distortion and power consumption can be calculated, plotted and exported for signal chains with up to 50 stages. ADIsimRF also includes an extensive data base of device models for ADI’s RF and mixed signal components.
ADF4208 Companion Parts
Recommended Linear Regulators
- For ultralow noise, 3V applications,150 mA output: ADP150.
- For high accuracy, 5V applications: ADP3334.
- For ultalow noise, 3V applications, 200 mA output: ADP151.
- For a step up, 3V to 5V regulator: ADP1613.
Recommended Divide-by-4 Prescaler
- For a low noise, low power, fixed RF block: ADF5001.
Recommended PLL Active Filter
- For an ultralow noise, rail-to-rail amplifier: OP184.
Technical Articles (4)
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.