LTC3803-3 Datasheet, PDF (3/16 Pages) Linear Technology – Constant Frequency Current Mode Flyback DC/DC Controller in ThinSOT

LTC3803-3
ELECTRICAL CHARACTERISTICS The ● indicates specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_CC = 8V, unless otherwise noted. (Note 2)
SYMBOL
DC_ON(MIN)
DC_ON(MAX)
t_RISE
t_FALL
I_SLMAX
t_SFST
PARAMETER
Minimum Switch On Duty Cycle
Maximum Switch On Duty Cycle
Gate Drive Rise Time
Gate Drive Fall Time
Peak Slope Compensation Output Current
Soft-Start Time
CONDITIONS
V_ITH/RUN = 1.3V, V_FB = 0.8V
V_ITH/RUN = 1.3V, V_FB = 0.8V
C_LOAD = 3000pF
C_LOAD = 3000pF (Note 7)
(Note 7)
MIN
TYP
MAX UNITS
8
9.6
%
70
80
90
%
40
ns
40
ns
5
μA
1.4
ms
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 LTC3803E-3 is guaranteed to meet specifications from 0°C to
85°C. Specifications over the – 40°C to 85°C operating temperature range
are assured by design, characterization and correlation with statistical
process controls. The LTC3803I-3 is guaranteed to meet performance
specifications over the –40°C to 125°C operating temperature range.
Note 3: T_J is calculated from the ambient temperature T_A and power
dissipation P_D according to the following formula:
T_J = T_A + (P_D • 230°C/W).
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency.
Note 5: The LTC3803-3 is tested in a feedback loop that servos V_FB to the
output of the error amplifier while maintaing I_TH/RUN 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 (R_SL). For
details, refer to the programmable slope compensation feature in the
Applications Information section.
Note 7: Guaranteed by design.
38033fa
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