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HMC704LP4E

v04.0215

For price, delivery and to place orders: Analog Devices, Inc., One Technology Way, Norwood, MA 02062

978-250-3343 tel • 978-250-3373 fax • Order online at www.analog.com/hittitemw

Application support: Phone: 978-250-3343 or RFMG-apps@analog.com

Theory of Operation

The PLL consists of the following functional blocks:

1.

Reference Path Input Buffer and ’R’ Divider

2. VCO Path Input Buffer, RF Divide-by-2 and Multi-Modulus ’N’ Divider

3. Δ

4. Phase Detector

5. Charge Pump

6. Main serial Port

7.

Lock Detect and Register Control

8. Auxiliary Output serial Port

9. Power On Reset Circuit

External VCO

The PLL charge pump can operate with the charge pump supply as high as 5.2V. The charge pump output at the varac-

tor tuning port, normally can maintain low noise performance to within 500 mV of ground or 800 mV of the upper supply

voltage.

High Performance Low Spurious Operation

The HMC704LP4E has been designed for the best phase noise and low spurious content possible in an integrated PLL.

spurious signals in a PLL can occur in any mode of operation and can come from a number of sources.

Figure of Merit Noise Floor and Flicker Noise Models

The phase noise of an ideal phase locked oscillator is dependent upon a number of factors:

a. Frequency of the VCO, and the Phase detector

b. VCO sensitivity, kvco, VCO and Reference Oscillator phase noise profiles

c. Charge Pump current, Loop Filter and Loop Bandwidth

d. Mode of Operation: Integer, Fractional modulator style

The contributions of the PLL to the output phase noise can be characterized in terms of a Figure of Merit (FOM) for both

the PLL noise floor and the PLL flicker (1/f) noise regions, as follows:

Figure 23. Synthesizer with External VCO

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responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other

rights of third parties that may result from its use. Specifications subject to change without notice. No

license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

Trademarks and registered trademarks are the property of their respective owners.

For price, delivery, and to place orders: Analog Devices, Inc.,

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106

Phone: 781-329-4700 • Order online at www.analog.com

Application Support: Phone: 1-800-ANALOG-D