HMC1197LP7FE datasheet(24/57 Pages) AD

24 / 57 page

For price, delivery, and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824

Phone: 978-250-3343

Fax: 978-250-3373

Order On-line at www.hittite.com

Application Support: Phone: 978-250-3343 or apps@hittite.com

HMC1197LP7FE

v03.0314

Wideband direct Quadrature Modulator

w/ Fractional-n Pll & Vco, 100 - 4000 MHz

1.3.1.4 Phase detector Functions

Phase detector register Reg 0Bhallows manual access to control special phase detector features.

Setting Reg 0Bh[5] = 0, masks the PD up output, which prevents the charge pump from pumping up.`

Setting (Reg 0Bh[6]) = 0, masks the PD down output, which prevents the charge pump from pumping

down.

Clearing both Reg 0Bh[5] and Reg 0Bh[6] tri-states the charge pump while leaving all other functions

operating internally.

PD Force UP Reg 0Bh[9] = 1 and PD Force DN Reg 0Bh[10] = 1 allows the charge pump to be forced up

or down respectively. This will force the VCO to the ends of the tuning range which can be useful in VCO

testing.

1.3.2

reference input Stage

Figure 39. Reference Path Input Stage

The reference buffer provides the path from an external reference source (generally crystal based) to

the R divider, and eventually to the phase detector. The buffer has two modes of operation controlled by

Reg 08h[21]. High Gain (Reg 08h[21] = 0), recommended below 200 MHz, and High frequency (Reg 08h[21]

= 1), for 200 to 350 MHz operation. The buffer is internally DC biased, with 100 Ω internal termination. For

50 Ω match, an external 100 Ω resistor to ground should be added, followed by an AC coupling capacitor

(impedance < 1 Ω), then to the XREFP pin of the part.

At low frequencies, a relatively square reference is recommended to keep the input slew rate high. At higher

frequencies, a square or sinusoid can be used. The following table shows the recommended operating

regions for different reference frequencies. If operating outside these regions the part will normally still

operate, but with degraded reference path phase noise performance.

Information furnished by Analog Devices is believed to be accurate and reliable. However, no

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

HMC1197LP7FE Fiches technique(PDF) 24 Page - Analog Devices