Datasheet LTC6905 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 17MHz to 170MHz Resistor Set SOT-23 Oscillator |
| Pages / Page | 12 / 1 — FEATURES. DESCRIPTION. One External Resistor Sets the Frequency. Fast … |
| File Format / Size | PDF / 175 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. One External Resistor Sets the Frequency. Fast Start-Up Time: 100μs Typical
Model Line for this Datasheet
- LTC6905CS5#PBF LTC6905CS5#TRMPBF LTC6905CS5#TRMPBF LTC6905CS5#TRPBF LTC6905CS5#TRPBF LTC6905HS5#PBF LTC6905HS5#TRMPBF LTC6905HS5#TRMPBF LTC6905HS5#TRPBF LTC6905HS5#TRPBF LTC6905IS5#PBF LTC6905IS5#TRMPBF LTC6905IS5#TRMPBF LTC6905IS5#TRPBF LTC6905IS5#TRPBF LTC6905MPS5#PBF LTC6905MPS5#TRMPBF LTC6905MPS5#TRMPBF LTC6905MPS5#TRPBF LTC6905MPS5#TRPBF
Text Version of Document
LTC6905 17MHz to 170MHz Resistor Set SOT-23 Oscillator
FEATURES DESCRIPTION
n
One External Resistor Sets the Frequency
The LTC®6905 precision, programmable silicon oscilla- n
Fast Start-Up Time: 100μs Typical
tor is easy to use and occupies very little board space. It n
Frequency Range: 17MHz to 170MHz
requires only a single resistor to set the output frequency n Frequency Error ±0.5% Typ 17MHz to 170MHz from 17MHz to 170MHz with a typical frequency error of (TA = 0°C to 70°C, Over All Settings) 0.5% or less. n ±20ppm/°C Temperature Stability The LTC6905 operates with a single 2.7V to 5.5V power n Rise Time: 0.5ns, CL = 5pF supply and provides a rail-to-rail, 50% duty cycle square n Timing Jitter: 7.2ps RMS at 170MHz wave output. The CMOS output driver ensures fast rise/fall n 50% ±2.5% Duty Cycle times and rail-to-rail switching. Operation is simple: A n 6mA Typical Supply Current, fOSC = 100MHz single resistor, RSET, between 10k to 25k is used to set n CMOS Output Drives 500Ω Load (VS = 3V) the frequency, and an internal three-state divider (DIV n Operates from a Single 2.7V to 5.5V Supply input) allows for division of the master clock by 1, 2 or 4, n Low Profi le (1mm) ThinSOT ™ Package providing three frequencies for each RSET value.
APPLICATIONS
The LTC6905 features a proprietary feedback loop that linearizes the relationship between RSET and frequency, n eliminating the need for tables to calculate frequency. The High Frequency Precision Oscillator n oscillator can be easily programmed using the simple High Speed Data Bus Clock n formula outlined below: Fixed Crystal Oscillator Replacement n Ceramic Oscillator Replacement ⎧1, DIV Pin = + V ⎛ 168. MHz 5 •1 k 0 Ω ⎞ 1 ⎪ L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. f = ⎜ + 1. MHz 5 • , N 2, DIV Pin = Open OSC ⎟ = ⎨ ThinSOT is a trademark of Linear Technology Corporation. ⎝ R ⎠ N SET ⎪ All other trademarks are the property of their respective owners. ⎩4, DIV Pin = GND Protected by U.S. Patents including 6614313, 6342817. For higher accuracy, fi xed frequency versions that include an internal frequency-setting resistor, see the LTC6905-XXX Series data sheet.
TYPICAL APPLICATION Typcial Distribution of Frequency Error, TA = 25°C
60 V+ = 3V RSET = 12k 50 DIV = 1
Basic Connection
40 17.225MHz ≤ fOSC ≤ 170MHz 5V 1 5 30 V+ OUT UNITS 0.1μF LTC6905 2 5V 10k ≤ R 20 SET ≤ 25k GND ÷1 3 4 ÷2 SET DIV OPEN 10 ÷4 6905 TA01 0 –0.5 –0.3 –0.1 0.1 0.3 0.5 % ERROR 6905 TA02 NOTE: RESISTOR, RSET, TOLERANCE WILL ADD TO THE FREQUENCY ERROR 6905fd 1
FEATURES DESCRIPTION
n
One External Resistor Sets the Frequency
The LTC®6905 precision, programmable silicon oscilla- n
Fast Start-Up Time: 100μs Typical
tor is easy to use and occupies very little board space. It n
Frequency Range: 17MHz to 170MHz
requires only a single resistor to set the output frequency n Frequency Error ±0.5% Typ 17MHz to 170MHz from 17MHz to 170MHz with a typical frequency error of (TA = 0°C to 70°C, Over All Settings) 0.5% or less. n ±20ppm/°C Temperature Stability The LTC6905 operates with a single 2.7V to 5.5V power n Rise Time: 0.5ns, CL = 5pF supply and provides a rail-to-rail, 50% duty cycle square n Timing Jitter: 7.2ps RMS at 170MHz wave output. The CMOS output driver ensures fast rise/fall n 50% ±2.5% Duty Cycle times and rail-to-rail switching. Operation is simple: A n 6mA Typical Supply Current, fOSC = 100MHz single resistor, RSET, between 10k to 25k is used to set n CMOS Output Drives 500Ω Load (VS = 3V) the frequency, and an internal three-state divider (DIV n Operates from a Single 2.7V to 5.5V Supply input) allows for division of the master clock by 1, 2 or 4, n Low Profi le (1mm) ThinSOT ™ Package providing three frequencies for each RSET value.
APPLICATIONS
The LTC6905 features a proprietary feedback loop that linearizes the relationship between RSET and frequency, n eliminating the need for tables to calculate frequency. The High Frequency Precision Oscillator n oscillator can be easily programmed using the simple High Speed Data Bus Clock n formula outlined below: Fixed Crystal Oscillator Replacement n Ceramic Oscillator Replacement ⎧1, DIV Pin = + V ⎛ 168. MHz 5 •1 k 0 Ω ⎞ 1 ⎪ L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. f = ⎜ + 1. MHz 5 • , N 2, DIV Pin = Open OSC ⎟ = ⎨ ThinSOT is a trademark of Linear Technology Corporation. ⎝ R ⎠ N SET ⎪ All other trademarks are the property of their respective owners. ⎩4, DIV Pin = GND Protected by U.S. Patents including 6614313, 6342817. For higher accuracy, fi xed frequency versions that include an internal frequency-setting resistor, see the LTC6905-XXX Series data sheet.
TYPICAL APPLICATION Typcial Distribution of Frequency Error, TA = 25°C
60 V+ = 3V RSET = 12k 50 DIV = 1
Basic Connection
40 17.225MHz ≤ fOSC ≤ 170MHz 5V 1 5 30 V+ OUT UNITS 0.1μF LTC6905 2 5V 10k ≤ R 20 SET ≤ 25k GND ÷1 3 4 ÷2 SET DIV OPEN 10 ÷4 6905 TA01 0 –0.5 –0.3 –0.1 0.1 0.3 0.5 % ERROR 6905 TA02 NOTE: RESISTOR, RSET, TOLERANCE WILL ADD TO THE FREQUENCY ERROR 6905fd 1
