TPS54331 Datasheet, PDF (1/24 Pages) Texas Instruments – 3A, 28V INPUT, STEP DOWN SWIFT™ DC/DC CONVERTER WITH Eco-mode

TPS54331
www.ti.com ....................................................................................................................................................................................................... SLVS839 – JULY 2008
3A, 28V INPUT, STEP DOWN SWIFT™ DC/DC CONVERTER WITH Eco-mode™
FEATURES
1
•2 3.5V to 28V Input Voltage Range
• Adjustable Output Voltage Down to 0.8V
• Integrated 80 mΩ High Side MOSFET Supports
up to 3A Continuous Output Current
• High Efficiency at Light Loads with a Pulse
Skipping Eco-mode™
• Fixed 570kHz Switching Frequency
• Typical 1µA Shutdown Quiescent Current
• Adjustable Slow Start Limits Inrush Currents
• Programmable UVLO Threshold
• Overvoltage Transient Protection
• Cycle by Cycle Current Limit, Frequency Fold
Back and Thermal Shutdown Protection
• Available in Easy-to-Use SOIC8 Package
• Supported by SwitcherPro™ Software Tool
(http://focus.ti.com/docs/toolsw/folders/print/s
witcherpro.html)
• For SWIFT™ Documentation, See the TI
Website at www.ti.com/swift
APPLICATIONS
• Consumer Applications such as Set-Top
Boxes, CPE Equipment, LCD Displays,
Peripherals, and Battery Chargers
• Industrial and Car Audio Power Supplies
• 5V, 12V and 24V Distributed Power Systems
SIMPLIFIED SCHEMATIC
Ren1
Ren2
EN
VIN
TPS54331
BOOT
PH
SS
COMP
C_SS
C₁
C₂
R₃
VSENSE
GND
VIN
C_I
C_BOOT
L_O
D1
C_O
VOUT
R_O1
R_O2
DESCRIPTION
The TPS54331 is a 28-V, 3-A non-synchronous buck
converter that integrates a low Rds(on) high side
MOSFET. To increase efficiency at light loads, a
pulse skipping Eco-mode™ feature is automatically
activated. Furthermore, the 1 µA shutdown supply
current allows the device to be used in battery
powered applications. Current mode control with
internal slope compensation simplifies the external
compensation calculations and reduces component
count while allowing the use of ceramic output
capacitors. A resistor divider programs the hysterisis
of the input under-voltage lockout. An overvoltage
transient protection circuit limits voltage overshoots
during startup and transient conditions. A cycle by
cycle current limit scheme, frequency fold back and
thermal shutdown protect the device and the load in
the event of an overload condition. The TPS54331 is
available in an 8-pin SOIC package that has been
internally optimized to improve thermal performance.
100
90
80
70
60
50
40
30
20
10
0
0.01
EFFICIENCY
V_I = 12 V
V_I = 18 V
V_I = 24 V
V_I = 28 V
V_I = 5 V
0.1
1
10
I_L - Load Current - A
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
SWIFT, Eco-mode, SwitcherPro are trademarks of Texas Instruments.
2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2008, Texas Instruments Incorporated