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LTC3805-5_15 Datasheet, PDF (4/20 Pages) Linear Technology – Adjustable Frequency Current Mode Flyback/ Boost/SEPIC DC/DC Controller
LTC3805-5
ELECTRICAL CHARACTERISTICS
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: The LTC3805-5 is tested under pulsed conditions such that
TJ ≈ TA. The LTC3805E-5 is guaranteed to meet specifications from
0°C to 85°C. Specifications over the –40°C to 85°C operating junction
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTC3805I-5 is guaranteed over the
–40°C to 125°C operating junction temperature range, the LTC3805H-5 is
guaranteed over the full –40°C to 150°C operating junction temperature
range and the LTC3805MP-5 is tested and guaranteed over the full –55°C
to 150°C operating temperature range. High junction temperatures
degrade operating lifetimes. Operating lifetime is derated at junction
temperatures greater than 125°C. Note that the maximum ambient
temperature consistent with these specifications is determined by specific
operating conditions in conjunction with board layout, the rated package
thermal resistance and other environmental factors.
Note 3: TJ is calculated from the ambient temperature TA and power
dissipation PD according to the following formula:
TJ = TA + (PD • 45°C/W)
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency.
Note 5: The LTC3805-5 is tested in a feedback loop that servos VFB to the
output of the error amplifier while maintaining ITH at the midpoint of the
current limit range.
Note 6: Peak current sense voltage is reduced dependent on duty cycle
and an optional external resistor in series with the SENSE pin. For
details, refer to Programmable Slope Compensation in the Applications
Information section.
Note 7: Guaranteed by design.
Note 8: Overcurrent threshold voltage is reduced dependent on an
optional external resistor in series with the OC pin. For details, refer to
Programmable Overcurrent in the Applications Information section.
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