SC411
POWER MANAGEMENT
Electrical Characteristics (Cont.)
25°C
Parameter
Conditions
Min
Soft-Start
Soft-Start Ramp Time
Under-Voltage Blank Time
Gate Drivers
Shoot-Through Delay
(4)
DL Pull-Down Resistance
DL Sink Current
DL Pull-Up Resistance
DL Source Current
DH or DL Rising
DL Low
DL = 2.5V
DL High
DL = 2.5V
30
0.80
3.1
2
1.3
4
1.75
ns
Ω
A
Ω
A
EN/PSV High to PGD High
EN/PSV High to UV High
440
440
clks
(3)
clks
(3)
Typ
Max
Min
Max
-40°C to 125°C
Units
Notes:
1) When the inductor is in continuous and discontinuous conduction mode, the output voltage will have a DC regulation level higher than the
error-comparator threshold by 50% of the ripple voltage.
2) Using a current sense resistor, this measurement relates to PGND minus the voltage of the source on the low-side MOSFET. These values
guaranteed by the ILIM Source Current and Current Comparator Offset tests.
3) clks = Switching cycles.
4) Guaranteed by design. See Shoot-Through Delay Timing Diagram on Page 8.
5) Semtech’s SmartDriver
TM
FET drive
fi
rst pulls DH high with a pull-up resistance of 10Ω (typ) until LX = 1.5V (typ). At this point, an additional
pull-up device is activated, reducing the resistance to 2Ω (typ). This negates the need for an external gate or boost resistor.
©
2007 Semtech Corp.
5
www.semtech.com
SEMTECH [ SEMTECH CORPORATION ]
