HMC835LP6GETR: Wideband Fractional-N PLL with Integrated VCO – Features, Pinout, and Applications

 The HMC835LP6GETR, manufactured by Analog Devices, is a high-performance wideband fractional-N Phase-Locked Loop (PLL) with an integrated Voltage-Controlled Oscillator (VCO). Designed for frequency synthesis applications, this highly integrated solution offers low phase noise, wide frequency range, and superior spurious performance in a compact 6x6 mm package.

Overview

The HMC835LP6GETR combines a fractional-N PLL and a VCO into a single low-power, surface-mount device, significantly simplifying RF system design. It supports output frequencies from 33 MHz to 4400 MHz, making it an ideal frequency synthesizer for high-performance wireless infrastructure, RF test equipment, and broadband communications systems.

Key Features

• Integrated wideband VCO and fractional-N PLL

• Output frequency range: 33 MHz to 4400 MHz

• Fractional-N and Integer-N synthesis modes

• Ultra-low phase noise and spurious output

• Industry-leading figure of merit (FOM): -230 dBc/Hz

• Programmable frequency ramping and modulation features

• 3-wire serial interface for configuration

• Lock detect and digital calibration

• Power supply: 3.3V (typical)

• Low power consumption

Functional Description

The HMC835LP6GETR’s integrated VCO spans multiple frequency bands, eliminating the need for external band-select components. The device supports both fractional-N and integer-N PLL modes and features programmable charge pump currents, loop filter settings, and output frequency dividers. These capabilities allow designers to tailor phase noise and bandwidth for optimal performance in diverse RF environments.

The internal VCO delivers high spectral purity and stability, while the PLL supports fast frequency hopping and modulation schemes such as FSK and chirp generation. Its SPI-compatible 3-wire interface allows full control of the synthesizer's configuration registers.

Pin Configuration

The HMC835LP6GETR is housed in a 32-lead QFN (leadless) package measuring 6mm x 6mm. It is optimized for surface mount assembly with good thermal characteristics. Key pins include:

• RF output (differential)

• VCO control

• Loop filter connections

• Serial interface (SDIO, SCLK, LE)

• Power supply and ground

Note: For detailed pinout and recommended PCB layout, refer to the official Analog Devices datasheet.

Applications

The HMC835LP6GETR is highly versatile and can be used in a wide range of RF and microwave systems, including:

• Point-to-point and point-to-multipoint radios

• Wireless base stations and backhaul

• RF instrumentation and test equipment

• Military and aerospace communications

• Broadband wireless access

• Satellite systems

• Clock generation and frequency translation

Performance Highlights

• Wide frequency coverage from 33 MHz to 4.4 GHz enables use across multiple RF bands

• Phase noise performance suitable for demanding LO applications

• Integration reduces BOM cost and board space

• Support for fast ramping and agile frequency synthesis

• SPI interface provides flexible configuration for digital systems

Summary

The HMC835LP6GETR from Analog Devices is a best-in-class wideband fractional-N PLL with an integrated VCO. It provides designers with an efficient path to high-performance frequency generation with minimal external components. With broad output coverage, low noise, and strong integration, it stands out as a powerful solution for modern RF design challenges.

For engineers and system architects seeking a flexible and compact frequency synthesizer, the HMC835LP6GETR offers unmatched performance and integration in a small form factor.