TPS22981
www.ti.com
SLVSBM6 –DECEMBER 2012
3.3V to 18V Thunderbolt Power Mux
Check for Samples: TPS22981
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FEATURES
DESCRIPTION
The TPS22981 is
providing a connection to a peripheral device from
either a low voltage supply (3V to 3.6V) or a high
voltage supply (4.5V to 19.8V). The desired output is
selected by digital control signals.
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Powered from 3.3V
a
current-limited power mux
4.5V to 19.8V High Voltage Switch
3V to 3.6V Switch
Adjustable Current Limit
Thermal Shutdown
The high voltage (VHV) and low voltage (V3P3)
switch current limits are set with external resistance.
Once the current limit is reached, the TPS22981 will
control the switch to maintain the current at this limit.
Make Before Break Switch
High Voltage Discharge Before Low Voltage
Make
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Reverse Current Blocking
When the high voltage supply is not present, the
TPS22981 will maintain the connection to the output
from the low voltage supply. Upon the presence of a
high voltage line and high voltage enable signal, the
high voltage switch is turned on in conjunction with
the low voltage switch until a reverse current is
detected through the low voltage switch, allowing a
seamless transition from low voltage to the high
voltage supply with minimal droop and shoot-through
current.
APPLICATIONS
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Notebook Computers
Desktop Computers
Power Management Systems
connector
To prevent current backflow during a switch over from
a
VHV connection to a V3P3 connection, the
TPS22981 will break the VHV connection, discharge
the output to approximately 3.3V and then make the
V3P3 connection. The output will transition to 0V
when a load is present, before returning to 3.3V.
RSET_S0
RSET_S3
RSET_V3P3
ISET_S0
ISET_S3
ENHVU
S0
V3P3OUT
V3P3
ISET_V3P3
VHV
The TPS22981 is available in a 4mm x 4mm x 1mm
QFN package.
Exposed Pad
DC/DC
V3P3
VHV
DC/DC
µC
Figure 1. Typical Application
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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