Datasheet

LTC3780
5
3780ff
For more information www.linear.com/LTC3780
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: T
J
for the QFN package is calculated from the temperature T
A
and
power dissipation P
D
according to the following formula:
T
J
= T
A
+ (P
D
• 34°C/W)
Note 3: The IC is tested in a feedback loop that servos V
ITH
to a specified
voltage and measures the resultant V
OSENSE
.
Note 4: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency.
Note 5: Rise and fall times are measured using 10% and 90% levels. Delay
times are measured using 50% levels.
Note 6: The minimum on-time condition is specified for an inductor
peak-to-peak ripple current ≥ 40% of I
MAX
(see minimum on-time
considerations in the Applications Information section).
Note 7: The LTC3780 is tested under pulsed load conditions such that T
J
≈
T
A
. The LTC3780E is guaranteed to meet specifications from 0°C to 85°C
junction temperature. Specifications over the –40°C to 85°C operating
junction temperature range are assured by design, characterization and
correlation with statistical process controls. The LTC3780I is guaranteed
over the –40°C to 125°C operating junction temperature range, and
the LTC3780MP is tested and guaranteed over the full –55°C to 125°C
operating junction temperature range.
Note 8: This parameter is guaranteed by design.
Note 9: f
OSC
is the running frequency for the application.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
PGOOD Output
∆V
FBH
PGOOD Upper Threshold V
OSENSE
Rising 5.5 7.5 10 %
∆V
FBL
PGOOD Lower Threshold V
OSENSE
Falling –5.5 –7.5 –10 %
∆V
FB(HYST)
PGOOD Hysteresis V
OSENSE
Returning 2.5 %
V
PGL
PGOOD Low Voltage I
PGOOD
= 2mA 0.1 0.3 V
I
PGOOD
PGOOD Leakage Current V
PGOOD
= 5V ±1 µA
elecTrical characTerisTics
The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are at T
A
= 25°C. (Note 7) V
IN
= 15V unless otherwise noted.