LTC6908-1/LTC6908-2

4

Rev C

For more information www.analog.com

RSET (Ω)

10k

5

4

3

2

1

0

–1

–2

–3

–4

–5

100k

1M

10M

690812 G01

TA = 25°C

TYPICAL MAX

GUARANTEED MAX

OVER TEMPERATURE

GUARANTEED MIN

OVER TEMPERATURE

TYPICAL MIN

RSET (Ω)

10k

5

4

3

2

1

0

–1

–2

–3

–4

–5

100k

1M

10M

690812 G02

TA = 25°C

TYPICAL MAX

GUARANTEED MAX

OVER TEMPERATURE

GUARANTEED MIN

OVER TEMPERATURE

TYPICAL MIN

TEMPERATURE (°C)

–40

20

60

690812 G03

–20

0

40

1.00

0.75

0.50

0.25

0

–0.25

–0.50

–0.75

–1.00

80

TYPICAL MAX

TYPICAL MIN

Frequency Error vs RSET,

V+ = 3V

Frequency Error vs RSET,

V+ = 5V

Frequency Error vs Temperature

Note 1: Stresses beyond those listed under Absolute Maximum Ratings

may cause permanent damage to the device. Exposure to any Absolute

Maximum Rating condition for extended periods may affect device

reliability and lifetime.

Note 2: LTC6908C and LTC6908I are guaranteed functional over the

operating temperature range of –40°C to 85°C.

Note 3: LTC6908C is guaranteed to meet specified performance from 0°C

to 70°C. The LTC6908C is designed, characterized and expected to meet

specified performance from –40°C to 85°C but is not tested or QA sampled

at these temperatures. The LTC6908I is guaranteed to meet the specified

performance limits from –40°C to 85°C. The LTC6908H is guaranteed to

meet the specified performance limits from –40°C to 125°C.

Note 4: Frequency accuracy is defined as the deviation from the fOUT

equation.

Note 5: Guaranteed by 5V test

Note 6: To conform to the Logic IC Standard, current out of a pin is

arbitrarily given a negative value.

Note 7: Output rise and fall times are measured between the 10% and the

90% power supply levels with no output loading. These specifications are

based on characterization.

Note 8: Long term drift on silicon oscillators is primarily due to the

movement of ions and impurities within the silicon and is tested at 30°C

under otherwise nominal operating conditions. Long term drift is specified

as ppm/√kHr due to the typically non-linear nature of the drift. To calculate

drift for a set time period, translate that time into thousands of hours, take

the square root and multiply by the typical drift number. For instance, a

year is 8.77kHr and would yield a drift of 888ppm at 300ppm/√kHr. Ten

years is 87.7kHr and would yield a drift of 2,809 ppm at 300 ppm/√kHr.

Drift without power applied to the device may be approximated as 1/10th

of the drift with power, or 30ppm/√kHr for a 300ppm/√kHr device.

TYPICAL PERFORMANCE CHARACTERISTICS

The l denotes the specifications which apply over the full operating

temperature range, otherwise specifications are at TA = 25°C. Test conditions are V+ = 2.7V to 5.5V, RL = 5k, CL = 5pF unless

otherwise noted. The modulation is turned off (MOD is connected to OUT2) unless otherwise specified. RSET is defined as the resistor

connected from the SET pin to the V+ pin.

VIL_MOD

Low Level MOD Input Voltage

l

0.4

V

IMOD

MOD Pin Input Current (Note 6)

MOD Pin = V+, V+ = 5V

MOD Pin = GND, V+ = 5V

l

l

–4

2

–2

4

µA

µA

VOH

High Level Output Voltage (Note 6)

(OUT1, OUT2)

V+ = 5V

IOH = –0.3mA

IOH = –1.2mA

l

l

4.75

4.4

4.9

4.7

V

V

V+ = 2.7V

IOH = –0.3mA

IOH = –0.8mA

l

l

2.35

1.85

2.6

2.2

V

V

VOL

Low Level Output Voltage (Note 6)

V+ = 5V

IOL = 0.3mA

IOL = 1.2mA

l

l

0.05

0.2

0.15

0.5

V

V

V+ = 2.7V

IOL = 0.3mA

IOL = 0.8mA

l

l

0.1

0.4

0.3

0.7

V

V

tr

Output Rise Time (Note 7)

V+ = 5V

V+ = 2.7V

6

11

ns

ns

tf

Output Fall Time (Note 7)

V+ = 5V

V+ = 2.7V

5

9

ns

ns

ELECTRICAL CHARACTERISTICS