Thermally Enhanced 14-Pin PowerPAD錚?/div>
HTSSOP Package Minimizes Board Area and
Junction Temperature Rise
APPLICATIONS
D
Multiphase Converters in Combination With
D
the TPS40090
Non-Isolated 3.3-V, 5-V and 12-V Input
dc-to-dc Converters for Processor Power,
General Computer, Telecom and Datacom
Applications
DESCRIPTION
The UCC27223 is a high-speed synchronous
buck drivers for today鈥檚 high-efficiency,
lower-output voltage designs. Using Predictive
Gate Drivet (PGD) control technology, these
drivers reduce diode conduction and reverse
recovery losses in the synchronous rectifier
MOSFET(s).
The UCC27223 includes an enable pin that
controls the operation of both outputs. A logic
latch is also included to keep both outputs low until
the first PWM input pulse comes in. The RDS(on)
of the SR pull-down sourcing device is also
minimized for higher frequency operations.
This closed loop feedback system detects
body-diode conduction, and adjusts deadtime
delays to minimize the conduction time interval.
This virtually eliminates body-diode conduction
while adjusting for temperature, load- dependent
delays, and for different MOSFETs. Precise gate
timing at the nanosecond level reduces the
reverse recovery time of the synchronous rectifier
MOSFET body-diode, reducing reverse recovery
losses seen in the main (high-side) MOSFET. The
lower junction temperature in the low-side
MOSFET increases product reliability. Since the
power dissipation is minimized, a higher switching
frequency can also be used, allowing for smaller
component sizes.
The UCC27223 is offered in the thermally
enhanced 14-pin PowerPADt package with
2擄C/W
胃
jc
.
FUNCTIONAL APPLICATION DIAGRAM
VIN
UCC27223
7
PWMIN
6,8 GND
3
2
VDD
ENBL
SW 11,12
G1 13
IN
VHI
14
VOUT
4,5 VLO
G2
9,10
GNDOUT
GNDIN
Note: 12-V input system shown. For 5-V input only systems, see Figure 6.
Predictive Gate Drivet and PowerPADt are trademarks of Texas Instruments Incorporated.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright
錚?/div>
2003, Texas Instruments Incorporated
www.ti.com
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