Low-Frequency, Spread-Spectrum EconOscillator

Industry's Only Spread-Spectrum Resistor-Programmable Oscillator


The DS1090 is a low-cost, dithered oscillator intended to be used as an external clock for switched-mode power supplies and other low-frequency applications. The dithering or sweeping function reduces peak-radiated emissions from the power supply at its fundamental frequency, as well as harmonic frequencies. The device consists of a resistor-programmed master oscillator, factory-programmed clock prescaler, and a pin-programmed dither circuit. These features allow the DS1090 to be used in applications where a spread-spectrum clock is desired to reduce radiated emissions. A combination of factory-set prescalers and external resistor allows for output frequencies ranging from 125kHz to 8MHz. Both dither frequency and dither percentage are set using control pins.
DS1090: Typical Operating Circuit DS1090: Typical Operating Circuit Enlarge+

Key Features

  • Low-Cost, Spread-Spectrum EconOscillator™
  • Simple User Programming
  • Output Frequency Programmable from 125kHz to 8MHz
  • Dither Percentage Programmable from 0% to 8%
  • Dither Rate Programmable (fMOSC / 512, 1024, 2048, or 4096)
  • 3.0V to 5.5V Single-Supply Operation
  • CMOS/TTL-Compatible Output
  • Operating Temperature Range: -40°C to +85°C


  • Embedded Microcontrollers
  • Industrial Controls
  • Printers
  • Servers
  • Switch-Mode Power Supplies
Part Number fOUT
User Prog. fOUT Spread Spectrum VCC
Reset Out Oper. Temp.
Package/Pins Budgetary
max min max See Notes
DS1090  8 125 ±2.5 (-40 to +85°C) External Resistors Yes 3.0 to 5.5 No -40 to +85
$0.83 @1k
See All Silicon Oscillators (19)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

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