TPS56921 Datasheet, PDF (1/39 Pages) Texas Instruments – 4.5V to 17V Input, 9A Synchronous Step Down SWIFT Converter With VID Control

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TPS56921
SLVSBL4 – OCTOBER 2012
4.5V to 17V Input, 9A Synchronous Step Down SWIFT™ Converter With VID Control
Check for Samples: TPS56921
FEATURES
1
• VID Control Range via I²C Compatible
Interface: 0.72V to 1.48V in 10mV Steps
• I²C Addressing Flexibility: 2 Bits by IC pins
• ±1.5% Output Voltage over Temperature for
VID Control
• ±1% Reference Voltage over Temperature for
External Regulation Mode
• Integrated 26mΩ / 19mΩ MOSFETs
• Power Input PVIN Voltage Range: 1.6V to 17V
• Switching Frequency: 200kHz to 1.6MHz
Internal Oscillator or Synchronizing to
External Clock
• Shutdown Current: 2µA
• Monotonic Start-Up into Pre-biased Output
Voltage
• Overcurrent Protection for Both MOSFETs
with Hiccup Mode for Severe Fault Conditions
• Thermal and Overvoltage Protection
• Adjustable Soft Start
• Power Good Monitor for Under- and Over-
Voltage Conditions
• Operating Junction Temperature Range: –40°C
to 125°C
• Available in 20-Pin HTSSOP Package with
PowerPAD^TM
APPLICATIONS
• Digital TVs
• Set Top Boxes
• SoC Power
• High Density Power Distribution Systems
DESCRIPTION
The TPS56921 in thermally enhanced 20-pin HTSSOP package is a full featured 17V, 9A synchronous step
down converter which is optimized for small designs through high efficiency and integrating the high-side and
low-side MOSFETs. After the initial power-up, the output voltage can be changed by codes sent to the IC via an
I²C compatible VID Control bus. Current mode control provides space savings and easy compensation.
The output voltage startup ramp is controlled by the SS pin which helps to control startup inrush current. Power
sequencing is supported by configuring the enable and the open drain power good pins. The output voltage is
user-configurable at startup by external voltage divider.
Cycle by cycle current limiting on the high-side fet protects the TPS56921 in overload situations and is enhanced
by a low-side sourcing current limit which prevents current runaway. There is also a low-side sinking current limit
which turns off the low-side MOSFET to prevent excessive reverse current. Hiccup protection will be triggered if
the overcurrent condition has persisted for longer than the preset time. Thermal hiccup protection disables the
part when die temperature exceeds thermal shutdown temperature and enables the part again after the built-in
thermal hiccup time.
SIMPLIFIED SCHEMATIC
EFFICIENCY
Fsw = 500 kHz, V_OUT= 1.1 V
VIN
PVIN PWRGD
VIN
Cboot
Cin
EN
BOOT
VDD
Rp2 Rp1
PH
SDA
SDA
SCL
ADDR1
ADDR0
Css Rrt
SCL
A1
VOUT
A0
VSENSE
SS
RT/CLK
COMP GND
R3
PowerPAD
Lo
Co
VOUT
R1
R2
100
90
80
70
V_IN = 5 V
60
V_IN = 12 V
50
40
30
20
10
0
0123456789
Output Current - A
C007
C1
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.
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 © 2012, Texas Instruments Incorporated