Features and Benefits
- LTC6908-1: Complementary Outputs (0°/180°)
- LTC6908-2: Quadrature Outputs (0°/90°)
- 50kHz to 10MHz Frequency Range
- One External Resistor Sets the Frequency
- Optional Spread Spectrum Frequency Modulation for Improved EMC Performance
- ±10% Frequency Spreading
- 400µA Supply Current Typical (V+ = 5V, 50kHz)
- Frequency Error ≤1.5% Max (TA = 25°C, V+ = 3V)
- ±40ppm/°C Temperature Stability
- Fast Start-Up Time: 260µs Typical (1MHz)
- Outputs Muted Until Stable
- Operates from a Single 2.7V to 5.5V Supply
- Available in Low Proﬁle (1mm) ThinSOT and DFN (2mm × 3mm) Packages
The LTC6908 is an easy-to-use precision oscillator that provides 2-outputs, shifted by either 180° or 90°. The oscillator frequency is programmed by a single external resistor (RSET) and spread spectrum frequency modulation (SSFM) can be activated for improved electromagnetic compatibility (EMC) performance.
The LTC6908 operates with a single 2.7V to 5.5V supply and provides rail-to-rail, 50% duty cycle square wave outputs. A single resistor from 10k to 2M is used to select an oscillator frequency from 50kHz to 10MHz (5V supply). The oscillator can be easily programmed using the simple formula outlined below:
fOUT =10MHz • 10k/RSET
The LTC6908’s SSFM capability modulates the output frequency by a pseudorandom noise (PRN) signal to decrease the peak electromagnetic radiation level and improve EMC performance. The amount of frequency spreading is ﬁxed at ±10% of the center frequency. When SSFM is enabled, the rate of modulation is selected by the user. The three possible modulation rates are fOUT/16, fOUT/32 and fOUT/64.
- Switching Power Supply Clock Reference
- Portable and Battery-Powered Equipment
- Precision Programmable Oscillator
- Charge Pump Driver
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Tools & Simulations
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
Models for the following parts are available in LTspice:
LTC6908-1 Companion Parts
Recommended Related Parts
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.