SC1405 Datasheet, PDF (1/12 Pages) Semtech Corporation – HIGH SPEED SYNCHRONOUS POWER MOSFET SMART DRIVER

HIGH SPEED SYNCHRONOUS POWER
MOSFET SMART DRIVER
SC1405
August 31, 2000
TEL:[phone] FAX:[phone] WEB:http://www.semtech.com
DESCRIPTION
The SC1405 is a Dual-MOSFET Driver with an internal
Overlap Protection Circuit to prevent shoot-through
from V_IN to GND in the main switching and syn-
chronous MOSFET’s. Each driver is capable of driving
a 3000pF load in 20ns rise/fall time and has ULTRA-
FAST propagation delay from input transition to the
gate of the power FET’s. The Overlap Protection circuit
ensures that the second FET does not turn on until the
top FET source has reached a voltage low enough to
prevent shoot-through. The delay between the bottom
gate going low to the top gate transitioning to high is
externally programmable via a capacitor for optimal
reduction of switching losses at the operating fre-
quency. The bottom FET may be disabled at light loads
by keeping S_MOD low to trigger asynchronous opera-
tion, thus saving the bottom FET’s gate drive current
and inductor ripple current. An internal voltage refer-
ence allows threshold adjustment for an Output Over-
Voltage protection circuitry, independent of the PWM
feedback loop. Under-Voltage-Lock-Out circuit is in-
cluded to guarantee that both driver outputs are low
when the 5V logic level is less than or equal to 4.4V
(typ) at supply ramp up (4.35V at supply ramp down). A
CMOS output provides status indication of the 5V sup-
ply. A low enable input places the IC in stand-by mode
thereby reducing supply current to less than 10µA.
SC1405 is offered in a high pitch (.025” lead spacing)
TSSOP package.
PIN CONFIGURATION
FEATURES
•= Fast rise and fall times (20ns typical with 3000pf
load)
•= 20ns max. Propagation delay (BG going low)
•= Adaptive/programmable shoot-through protection
•= Wide input voltage range (4.5-25V)
•= Programmable delay between MOSFET’s
•= Power saving asynchronous mode control
•= Output overvoltage protection/overtemp shutdown
•= Under-Voltage lock-out and power ready signal
•= Less than 10µA stand-by current (EN=low)
•= Power ready output signal
APPLICATIONS
•= High Density/Fast transient power supplies
•= Motor Drives/Class-D amps
•= High frequency (to 1.2 MHz) operation allows use
of small inductors and low cost caps in place of
electrolytics
•= Portable computers
ORDERING INFORMATION
DEVICE⁽¹⁾
PACKAGE TEMP. RANGE (T_J)
SC1405TS.TR TSSOP-14
0 - 125°C
Note:
(1) Only available in tape and reel packaging. A reel
contains 2500 devices.
BLOCK DIAGRAM
Top View
(14-Pin TSSOP)
© 2000 SEMTECH CORP.
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