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

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HMC993LP5E

v00.0911

RF AUTOMATIC GAIN CONTROLLER

(RF-AGC), 700 - 3000 MHz

Application Information

Introduction

The HMC993LP5E is a complete high performance Automatic Gain Control (AGC) solution, housing a Variable Gain

Amplifier (VGA) core and a control core in a single package. Its unique VVA technology provides constant OIP3 over

the entire control voltage range. The HMC993LP5E greatly simplifies the design of gain control loops by increasing

the integration level and reducing the number of required circuit elements. The VGA core of the HMC993LP5E is

composed of two identical voltage variable attenuators followed by two gain block amplifiers which operate from 0.7

to 3.0 GHz. The HMC993LP5E’s control core features a high accuracy log detector. As shown in the functional block

diagram, the HMC993LP5E combines all of these cores in a highly compact 5 x 5 mm plastic package, and offers an

easy-to-use, temperature stable AGC solution.

The HMC993LP5’s VGA core has a flexible structure where a single attenuator (22.2 dB at 1900 MHz) or two attenu-

ators (33.6 dB at 1900 MHz) can be used depending upon the dynamic range requirement. Inputs and outputs of

the HMC993LP5E’s attenuators and first amplifier (ATTIN1, ATTOUT1, ATTIN2, ATTOUT2, AMPIN1, AMPOUT1) are

broadband matched to 50 Ohm single-ended and require only external DC blocking capacitors over the entire fre-

quency band of operation. The input of the HMC993LP5E’s log detector (RFDETIN) is also broadband matched to 50

Ohm single-ended and does not require any matching components. Input and output of the HMC993LP5E’s second

amplifier (AMPIN2, AMPOUT2) need power matching components for key application frequencies. Refer to applica-

tion circuits for example application frequencies.

The HMC993LP5E requires a single 5V supply with adequate power supply decoupling as recommended in the appli-

cation schematics.

Figure 1a: The HMC993LP5E’s VGA configuration with 1 attenuator, 1900 MHz tune.