LTC6905

1

6905fa

, LTC and LT are registered trademarks of Linear Technology Corporation. ThinSOT is a

trademark of Linear Technology Corporation. All other trademarks are the property of their

respective owners. Protected by U.S. Patents, including 6614313, 6342817.

■

Frequency Range: 17MHz to 170MHz

■

50% ±2.5% Duty Cycle

■

Operates from a Single 2.7V to 5.5V Supply

17MHz to 170MHz

Resistor Set SOT-23 Oscillator

■

Ceramic Oscillator Replacement

The LTC

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

frequency, and an internal three-state divider (DIV input)

allows for division of the master clock by 1, 2 or 4,

The LTC6905 features a proprietary feedback loop that

eliminating the need for tables to calculate frequency. The

oscillator can be easily programmed using the simple

formula outlined below:

f

MHz

k

R

MHz

N

N

Open

OSC

SET

=

Ω

+

⎛

⎝

⎜

⎞

⎠

⎟

=

⎧

⎨

⎪

⎩

⎪

=

=

=

+

168 5

10

15

1

1

2

4

.•

.• ,

,

,

,

DIV Pin

V

DIV Pin

DIV Pin

GND

For higher accuracy, fixed frequency versions that include

an internal frequency-setting resistor, see the LTC6905-

XXX Series datasheet.

Basic Connection

DESCRIPTIO

FEATURES

APPLICATIO S

TYPICAL APPLICATIO

1

2

3

5

5V

5V

0.1µF

6905 TA01

4

GND

LTC6905

SET

OUT

DIV

OPEN

÷2

÷1

÷4

% ERROR

–0.5

0

10

20

30

40

50

60

TO THE FREQUENCY ERROR

–0.3

–0.1

0.1

0.3

6905 TA02

0.5

DIV = 1