SC420
POWER MANAGEMENT
POWER MANAGEMENT
Description
The SC420 is a cost effective Dual MOSFET Driver, in-
corporating Semtech’s patented Combi-Sense
TM
technol-
ogy, designed for switching High and Low side Power
MOSFETs in Step-down Switching regulators. A 20ns max
propagation delay from input transition to the gate of
the power FET’s guarantees operation at high switching
frequencies. Internal overlap protection circuit prevents
shoot-through from Vin to GND in the main and synchro-
nous MOSFETs.
High current drive capability (2A peak) allows fast
switching, thus reducing switching losses at high (up to
1.5MHz) frequencies without causing thermal stress on
the driver.
High Speed, Combi-Sense
TM
, Synchronous
Power MOSFET Driver for Mobile Applications
TARGET
Features
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High efficiency
Shutdown mode for increased power saving
Tri-state capability
Fast rise and fall times (15ns typical with 3000pF
load)
5V gate drive
Ultra-low (<20ns) propagation delay (BG going low)
Adaptive and programmable non-overlapping gate
drives provide shoot-through protection
Floating top drive switches up to 27V
High frequency (to 1.5 MHz) operation allows use
of small inductors and low cost ceramic capacitors
Under-voltage lockout
Low quiescent current
MLP packaging provides superior thermal perfor-
mance in a small footprint
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The high voltage CMOS process allows operation up to
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27 Volts, making the SC420 suitable for adaptor pow-
ered applications. Under-voltage-lockout and over-tem-
perature shutdown features are included for proper and
safe operation. The SC420 is offered in a space saving
MLP-12 package.
Applications
Conceptual Application Circuit
VIN2
u
High efficiency portable and notebook computers
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Battery powered applications
VIN
D1
M1
VIN
VIN2
VIN
TG
PWM
CO
BST
FB
Combi-Sense
TM
Controller IC
SC420
EN
DRN
BG
CDELAY
VPN
CBST
L1
VOUT
EN
GND
CS- CS+
M2
RVPN
CVPN
CDELAY
CL
Figure 1
Rev 4. December 2003
1
United States Patent No. 6,441,597
www.semtech.com
SEMTECH [ SEMTECH CORPORATION ]
