Analog Devices Inc./Maxim Integrated DS1086U+T

Overview

The DS1086U+T from Maxim Integrated is a spread-spectrum programmable clock generator producing dithered square-wave outputs from 260kHz to 133MHz. It features nonvolatile EEPROM configuration, 2% or 4% selectable frequency dithering, and dual control inputs (PDN for power-down, OE for glitchless output enable). It operates from a 5V supply and is used in EMI-sensitive digital systems such as printers, cable modems, and PC peripherals.

For engineers reviewing the DS1086U+T datasheet, DS1086U+T pinout, DS1086U+T application, or DS1086U+T equivalent, key selection considerations include its spread-spectrum dithering capability, 2-wire serial programmability, factory-default 97.1MHz output, 10kHz DAC step resolution, and µSOP-8 packaging for space-constrained timing designs.

Technical Context

The DS1086U+T integrates a voltage-controlled master oscillator (66–133MHz), a 10-bit DAC with 10kHz step size, an OFFSET register selecting one of 13 frequency subranges, and a prescaler dividing by 2^x (x = 0–8). Its dither is generated via a triangle-wave modulator injected into the VCO control path, with peak deviation fixed at 2% or 4% depending on the J0 bit in the PRESCALER register.

Configuration is performed over a 2-wire interface compliant with both standard (100kHz) and fast-mode (400kHz) I²C protocols. All settings-including DAC, OFFSET, PRESCALER, and ADDR-are stored in NV EEPROM; the device boots autonomously without external programming. Power-down mode reduces current to 35µA while retaining register state.

Key Specifications

Pinout & Package

DS1086U+T is housed in an 8-pin µSOP package (2.0mm × 3.0mm, 0.5mm pitch), RoHS-compliant and lead(Pb)-free.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable spread-spectrum clock generator applications.

Compared with IDT 8T49N241 and Si5351A, the DS1086U+T uniquely combines 5V operation, factory-trimmed dither control, zero-external-component design, and guaranteed EMI reduction - making it optimal for cost-sensitive, space-constrained commercial electronics where certified spread-spectrum behavior is required.

Availability

DS1086U+T is available at Aetrix Electronics and suitable for printers, cable modems, and PC peripherals requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for DS1086U+T 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

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and timing ICs for industrial, communications, and consumer applications.

The DS1086U+T belongs to the EconOscillator™ family - engineered specifically for EMI reduction in cost-sensitive digital systems using deterministic spread-spectrum clocking without external components.

FAQ

What is the factory-default output frequency of the DS1086U+T?

The DS1086U+T ships with a factory-default master oscillator frequency of 97.1MHz, resulting in a 97.1MHz output when the prescaler is set to divide-by-1 (PRESCALER = 00h). This value is stored in the RANGE register and corresponds to the OS (Offset Select) default setting. The device powers up and begins oscillating at this frequency without any external programming required.

Does the DS1086U+T require an external crystal or resonator?

No, the DS1086U+T does not require any external timing components. It contains a fully integrated voltage-controlled oscillator (VCO) and all necessary circuitry to generate its 66–133MHz master oscillator signal internally. The only external components needed are decoupling capacitors (0.1µF and 0.01µF) on the VCC pin, as specified in the typical operating circuit.

How is dither amount selected on the DS1086U+T?

Dither amount (2% or 4%) is selected via the J0 bit in the PRESCALER register (address 02h). When J0 = 1, 2% peak dither is applied; when J0 = 0, 4% peak dither is applied. The SPRD pin provides hardware override: when high, dither is enabled per J0 setting; when low, dither is disabled regardless of register state. Both methods are supported simultaneously.

Can the DS1086U+T operate in stand-alone mode without I²C communication?

Yes, the DS1086U+T is designed for stand-alone operation. Once programmed, its EEPROM retains all register settings (DAC, OFFSET, PRESCALER, etc.), allowing it to power up and generate the configured output frequency without any I²C activity. SDA and SCL pins may be tied high if in-circuit programming is never required - including during production testing - as explicitly noted in the datasheet.

What is the power-up behavior of the DS1086U+T output?

On power-up, the DS1086U+T holds the OUT pin in high-impedance state until power stabilizes and the internal oscillator completes ~512 cycles (approximately 0.1–0.5ms depending on frequency). Only then does the output become active. This ensures clean startup without glitches, and the OE and PDN pins remain functional throughout - enabling controlled enablement after stabilization.