Features

• One External Resistor Sets the Frequency
• Fast Start-Up Time: 100µs Typical
• Frequency Range: 17MHz to 170MHz
• Frequency Error ±0.5% Typ 17MHz to 170MHz
  (T_A = 0°C to 70°C, Over All Settings)
• ±20ppm/°C Temperature Stability
• Rise Time: 0.5ns, C_L = 5pF
• Timing Jitter: 7.2ps RMS at 170MHz
• 50% ±2.5% Duty Cycle
• 6mA Typical Supply Current, f_OSC = 100MHz
• CMOS Output Drives 500Ω Load (VS = 3V)
• Operates from a Single 2.7V to 5.5V Supply
• Low Profile (1mm) ThinSOT Package

Typical Application

Description

The LTC6905 precision, programmable silicon oscillator is easy to use and occupies very little board space. It requires only a single resistor to set the output frequency from 17MHz to 170MHz with a typical frequency error of 0.5% or less.

The LTC6905 operates with a single 2.7V to 5.5V power supply and provides a rail-to-rail, 50% duty cycle square wave output. The CMOS output driver ensures fast rise/fall times and rail-to-rail switching. Operation is simple: A single resistor, R_SET, between 10K to 25K is used to set the frequency, and an internal three-state divider (DIV input) allows for division of the master clock by 1, 2 or 4, providing three frequencies for each R_SET value.

The LTC6905 features a proprietary feedback loop that linearizes the relationship between R_SET and frequency, eliminating the need for tables to calculate frequency. The oscillator can be easily programmed using the simple formula outlined below:

See first page of Data Sheet for formula 

For higher accuracy, fixed frequency versions that include
an internal frequency-setting resistor, see the LTC6905-XXX Series datasheet.