50MHz to 1000MHz High-Linearity, Serial/Parallel-Controlled Analog/Digital VGA

The MAX2065 high-linearity, analog/digital variable-gain amplifier (VGA) is designed to operate in the 50MHz to 1000MHz frequency range with two independent attenuators (see the Typical Application Circuit in the full data sheet). The digital attenuator is controlled as a slave peripheral using either the SPI™-compatible interface or a parallel bus with 31dB total adjustment range in 1dB steps. An added feature allows "rapid-fire" gain selection between each of four steps, preprogrammed by the user through the SPI-compatible interface. The 2-pin control allows the user to quickly access any one of four customized attenuation states without reprogramming the SPI bus. The analog attenuator is controlled using an external voltage or through the SPI-compatible interface using an on-chip 8-bit DAC.

Because each of the three stages has its own RF input and RF output, this component can be configured to either optimize NF (amplifier configured first), OIP3 (amplifier last), or a compromise of NF and OIP3. The device's performance features include 22dB amplifier gain (amplifier only), 6.5dB NF at maximum gain (includes attenuator insertion losses), and a high OIP3 level of +42dBm. Each of these features makes the MAX2065 an ideal VGA for numerous receiver and transmitter applications.

In addition, the MAX2065 operates from a single +5V supply with full performance, or a single +3.3V supply with slightly reduced performance, and has an adjustable bias to trade current consumption for linearity performance. This device is available in a compact 40-pin thin QFN package (6mm x 6mm) with an exposed pad. Electrical performance is guaranteed over the extended temperature range (TC = -40°C to +85°C).

Applications

* Cable Modem Termination Systems (CMTS) * Cellular Band WCDMA and cdma2000® Base Stations * Fixed Broadband Wireless Access * GSM 850/GSM 900 EDGE Base Stations * IF and RF Gain Stages * Military Systems * Temperature Compensation Circuits * Video-on-Demand (VOD) and DOCSIS®-Compliant Edge QAM Modulation * WiMAX and LTE Base Stations and Customer Premise Equipment * Wireless Local Loop

* 50MHz to 1000MHz RF Frequency Range

* Pin-Compatible Family Includes:

* MAX2066 (Digital VGA)

* MAX2067 (Analog VGA)

* +19.4dB (Typ) Maximum Gain

* 0.5dB Gain Flatness Over 100MHz Bandwidth

* 62dB Gain Range (31dB Analog + 31dB Digital)

* Built-in DAC for Analog Attenuation Control

* Supports Four "Rapid-Fire" Preprogrammed Attenuator States

* Quickly Access Any One of Four Customized Attenuation States Without Reprogramming the SPI Bus

* Ideal for Fast-Attack, High-Level Blocker Protection

* Prevents ADC Overdrive Condition

* Excellent Linearity (Configured with Amplifier Last)

* +42dBm OIP3

* +63dBm OIP2

* +19dBm Output 1dB Compression Point

* -67dBc HD2

* -83dBc HD3

* 6.5dB Typical Noise Figure (NF)

* Fast, 25ns Digital Switching

* Very Low Digital VGA Amplitude Overshoot/Undershoot

* Single +5V Supply (Optional +3.3V Operation)

* External Current-Setting Resistors Provide Option for Operating Device in Reduced-Power/Reduced-Performance Mode