Analog Devices Inc. HMC1031MS8ETR

Overview

HMC1031MS8ETR from Analog Devices is an integer-N PLL clock generator IC designed for low-jitter reference clock synthesis and jitter attenuation in precision timing systems. It supports 0.1 MHz to 500 MHz VCOIN input, 140 MHz phase detector rate, hardware-selectable 1×/5×/10× multiplication, and operates in an 8-lead MSOP package at 3.3 V supply.

For engineers reviewing the HMC1031MS8ETR datasheet, HMC1031MS8ETR pinout, HMC1031MS8ETR application, or HMC1031MS8ETR equivalent, key selection criteria include its 50 µA charge pump current enabling narrow-loop-filter jitter attenuation, lock detect output for system synchronization monitoring, and power-down mode consuming only 0.8 µA at 85°C - critical for low-power OCXO multiplier and ADC/DAC clocking designs.

Technical Context

The HMC1031MS8ETR integrates a low-power integer-N divider (N = 1/5/10) controlled by CMOS pins D0/D1, eliminating serial programming overhead. Its phase-frequency detector (PFD) operates up to 140 MHz with a dedicated charge pump (CP) output capable of 0.2 V to VCC − 0.4 V compliance range.

It requires external ac-coupled REFIN (0.1–140 MHz) and VCOIN (up to 500 MHz) signals, and relies on an external loop filter and VCXO to form a complete jitter-attenuating PLL. The LKDOP pin delivers CMOS-level lock status with 3 mA drive capability, while power-down mode tristates all inputs and outputs.

Key Specifications

Pinout & Package

The HMC1031MS8ETR is housed in an 8-lead MSOP package (4.9 mm × 3.0 mm, HRM-8-1), RoHS-compliant and JEDEC MO-187-AA qualified.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PLL clock generator applications.

Compared with LMK04828BISQE/NOPB and Si5341-B-GM, the HMC1031MS8ETR offers the lowest active and standby power, simplest hardware-based configuration, and best jitter floor per milliwatt - making it optimal for cost-sensitive, single-output, battery-aware or thermally constrained jitter-cleaning roles.

Availability

HMC1031MS8ETR is available at Aetrix Electronics and suitable for OCXO multiplier, ADC/DAC clock cleaning, low-power test equipment, telecom base station reference synthesis, and precision instrumentation requiring stable component supply across extended temperature ranges.

Supply support for HMC1031MS8ETR 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 digital signal processing semiconductors, headquartered in Norwood, MA.

The HMC1031MS8ETR belongs to Analog Devices' Hittite Microwave PLL product line, engineered specifically for low-jitter, low-power, hardware-configurable clock generation in RF, instrumentation, and communications infrastructure.

FAQ

What is the minimum reference input frequency supported by the HMC1031MS8ETR?

The HMC1031MS8ETR supports a minimum reference input frequency of 0.1 MHz. This lower limit is determined by external AC coupling capacitor sizing relative to the device's 3.6 kΩ input impedance and board termination. At 0.1 MHz, a ≥10 µF capacitor is typically required to maintain sufficient signal coupling without excessive attenuation.

Does the HMC1031MS8ETR require an external loop filter, and what are its key design constraints?

Yes, the HMC1031MS8ETR requires an external passive loop filter between the CP pin and VCXO tuning input. Key constraints include: use of low-leakage MLCCs (e.g., Murata GRM series) to avoid false lock-detect failures; total leakage <1.5 µA for 10 MHz reference; and charge pump current fixed at 50 µA - enabling compact capacitor values (e.g., 220 nF) even for sub-10 Hz bandwidths.

How does the lock detect function work on the HMC1031MS8ETR, and what can cause false unlock indications?

The HMC1031MS8ETR lock detect compares arrival times of divided VCO and reference edges at the PFD; it asserts LKDOP high when phase offset stays within ±3 ns. False unlock indications occur primarily due to excessive leakage current on the CP node - including MLCC dielectric absorption, VTUNE pin DC current, or PCB contamination - which introduces static phase offset exceeding the 3 ns window.

Can the HMC1031MS8ETR drive a 500 MHz VCXO directly, and what input signal requirements apply?

Yes, the HMC1031MS8ETR supports VCOIN frequencies up to 500 MHz. The VCOIN input must be AC-coupled, with peak voltage ≤ VCC + 0.4 V, DC bias ≈ 1.65 V, and input swing between 0.1 V and 3.5 V p-p. Performance is guaranteed in the recommended operating region shown in Figure 19 of the datasheet, validated across temperature and process corners.

What are the exact pin configurations for selecting divide-by-5 operation on the HMC1031MS8ETR?

To configure divide-by-5 on the HMC1031MS8ETR, set D0 = 0 (low) and D1 = 1 (high) per Table 4. These are CMOS-level inputs referenced to VCC; D0 and D1 must be driven actively - floating states are undefined. Pull-down resistors (e.g., 10 kΩ to GND) ensure default power-down (D0=0, D1=0) if unused, preventing unintended operation during startup.