Analog Devices Inc. HMC700LP4E

Overview

HMC700LP4E from Analog Devices (formerly Hittite Microwave) is a SiGe BiCMOS fractional-N phase-locked loop (PLL) synthesizer designed for ultra-low-phase-noise frequency synthesis with external VCOs. It supports RF input up to 8 GHz, operates in both fractional and integer modes, delivers -103 dBc/Hz phase noise at 20 kHz offset (fractional mode, 6 GHz VCO, 50 MHz PFD), and features 24-bit step resolution (3 Hz typical). It is used in high-performance wireless infrastructure transceivers requiring fast frequency hopping and low spurious generation.

For engineers reviewing the HMC700LP4E datasheet, HMC700LP4E pinout, HMC700LP4E application, or HMC700LP4E equivalent, key selection considerations include its 8 GHz RF input capability, dual-mode (fractional/integer) operation, cycle-slip prevention for rapid tuning, 24-bit frequency resolution, and strict analog/digital supply separation (3.3 V and 5 V rails).

Technical Context

The HMC700LP4E implements a delta-sigma modulator architecture enabling fine frequency resolution and low fractional spurs. Its phase-frequency detector (PFD) incorporates cycle-slip prevention logic to reduce frequency-hopping latency, while its precision charge pump (5 V supplies) maintains linearity critical for fractional-mode stability.

It uses separate 3.3 V analog/digital supplies and dedicated 5 V charge pump rails (VDDCP/VCCCP), with internal biasing (1.92 V ±20 mV on BIAS pin) and differential RF/reference inputs. The 16-bit prescaler and 14-bit reference divider support wide N/R ratio flexibility across 100 MHz–8 GHz RF and 200 kHz–200 MHz reference ranges.

Key Specifications

Pinout & Package

24-lead, 4 mm × 4 mm LFCSP package (16 mm² footprint) with exposed thermal paddle; RoHS-compliant, reflow-compatible (260 °C peak, 40 sec).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fractional-N PLL synthesizer applications.

Compared with ADF4371BCPZ and LMS8001TR, the HMC700LP4E uniquely combines external VCO interface, 5 V charge pump capability, cycle-slip prevention, and sub-105 dBc/Hz phase noise at 8 GHz - making it optimal for infrastructure-grade microwave synthesizers where performance trumps integration.

Availability

HMC700LP4E is available at Aetrix Electronics and suitable for base station transceivers, WiMAX CPE, phased array radar, and test & measurement equipment requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for HMC700LP4E includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and RF semiconductors, serving communications, industrial, and aerospace markets with precision timing and signal processing solutions.

The HMC700LP4E belongs to Analog Devices' high-frequency PLL portfolio, developed specifically for microwave infrastructure applications demanding ultra-low phase noise, fast frequency agility, and robust external VCO interfacing.

FAQ

What is the maximum RF input frequency supported by the HMC700LP4E?

The HMC700LP4E supports a maximum RF input frequency of 8 GHz under 3.3 V supply conditions. This specification is confirmed in the Electrical Specifications table (page 0-2), where "Max RF Input Frequency (3.3V)" is listed as 8 GHz (typical) and 9 GHz (maximum). Operation beyond 8 GHz may compromise phase noise, spurious performance, or lock stability depending on VCO drive level and board layout.

Does the HMC700LP4E integrate a VCO, or does it require an external one?

The HMC700LP4E requires an external VCO. It is explicitly described as a "synthesizer with External VCO" in the Theory of Operation section (page 0-6), and its RF input pins (RFIP/RFIN) are designed for AC-coupled connection to an external oscillator. No internal VCO is present - the device functions solely as a fractional-N PLL core with prescaler, PFD, charge pump, and dividers.

What are the supply voltage requirements for the HMC700LP4E charge pump?

The HMC700LP4E requires two dedicated 5 V supplies for the charge pump: VDDCP (digital charge pump supply) and VCCCP (analog charge pump supply). Both must be equal and within 4.5–5.5 V per the Electrical Specifications (page 0-3). These rails are independent of the 3.3 V analog/digital supplies and enable higher tuning voltage swing and improved charge pump linearity - critical for low fractional spurs.

How does the HMC700LP4E achieve fast frequency hopping without cycle slips?

The HMC700LP4E implements Cycle Slip Prevention (CSP) technology in its phase-frequency detector. As documented in the General Description (page 0-2) and Figure 5 (page 0-5), CSP dynamically adjusts PFD timing during large N-divider transitions to maintain phase continuity. This prevents loss of lock and reduces settling time - demonstrated in a 5200→3950 MHz hop where CSP reduces transient duration versus CSP-OFF operation.

Can the HMC700LP4E operate in both fractional and integer-N modes, and what are the key differences in performance?

Yes, the HMC700LP4E supports both fractional and integer-N modes. In fractional mode, it achieves 3 Hz typical step resolution and -103 dBc/Hz phase noise (6 GHz, 20 kHz offset); in integer mode, phase noise improves to -108 dBc/Hz but step size is coarser (determined by PFD frequency and N-divider). Fractional mode enables fine channel spacing but requires careful loop filter design to suppress fractional spurs; integer mode offers lowest phase noise for fixed-frequency LO generation.