ADF4151 datasheet(8/28 Pages) AD

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ADF4151

Data Sheet

Rev. B | Page 8 of 28

Pin No.

Mnemonic

Description

RSET

Connecting a resistor between this pin and GND sets the charge pump output current. The nominal voltage

bias at the RSET pin is 0.49 V. The relationship between ICP and RSET is

SET

22.95

where:

RSET

= 5.1 kΩ.

ICP = 4.5 mA.

Lock Detect Output Pin. This pin outputs a logic high to indicate PLL lock; a logic low output indicates loss of PLL

lock.

26, 27

DGND

Digital Ground. Ground return path for DVDD.

DVDD

Digital Power Supply. This pin should be the same voltage as AVDD. Decoupling capacitors to the ground plane

should be placed as close as possible to this pin.

REFIN

Reference Input. This is a CMOS input with a nominal threshold of VDD/2 and a dc equivalent input resistance

of 100 kΩ. This input can be driven from a TTL or CMOS crystal oscillator, or it can be ac-coupled.

MUXOUT

Multiplexer Output. This multiplexer output allows either the lock detect, the scaled RF, or the scaled reference

frequency to be accessed externally.

SDGND

Digital Sigma-Delta (Σ-Δ) Modulator Ground. Ground return path for the Σ-Δ modulator.

SDVDD

Power Supply Pin for the Digital Σ-Δ Modulator. Should be the same voltage as AVDDx. Decoupling capacitors

to the ground plane are to be placed as close as possible to this pin.

The exposed pad must be connected to GND.

ADF4151 Datasheet(PDF) 8 Page - Analog Devices