GENERAL DESCRIPTION

The ADF4157 is a 6 GHz fractional-N frequency synthesizer with a 25-bit fixed modulus, allowing subhertz frequency resolution at 6 GHz. It consists of a low noise digital phase frequency detector (PFD), a precision charge pump, and a programmable reference divider. There is a Σ-Δ based fractional interpolator to allow programmable fractional-N division. The INT and FRAC values define an overall N divider, N = INT + (FRAC/225). The ADF4157 features cycle slip reduction circuitry, which leads to faster lock times without the need for modifications to the loop filter.

FEATURES

RF bandwidth to 6 GHz

25-bit fixed modulus allows subhertz frequency resolution

2.7 V to 3.3 V power supply

Separate VP allows extended tuning voltage

Programmable charge pump currents

3-wire serial interface

Digital lock detect

Power-down mode

Pin compatible with the following frequency synthesizers:

ADF4110/ADF4111/ADF4112/ADF4113/

ADF4106/ADF4153/ADF4154/ADF4156

Cycle slip reduction for faster lock times

APPLICATIONS

Satellite communications terminals, radar equipment

Instrumentation equipment

Personal mobile radio (PMR)

Base stations for mobile radio

Wireless handsets

ADF4157屬于集成電路（IC） > 時(shí)鐘發(fā)生器，PLL，頻率合成器。亞德諾半導(dǎo)體技術(shù)有限公司制造生產(chǎn)的ADF4157時(shí)鐘發(fā)生器，PLL，頻率合成器時(shí)鐘發(fā)生器、PLL 和頻率合成器集成電路 (IC) 可為邏輯器件提供參考信號(hào)的穩(wěn)定定時(shí)脈沖，這些器件包括計(jì)算機(jī)、微控制器、數(shù)據(jù)通信系統(tǒng)和圖形/視頻發(fā)生器。這些集成電路可能包括緩沖器、驅(qū)動(dòng)器、分頻器、倍頻器、多路復(fù)用器、合成器、扇出分配器和預(yù)分頻器。