TPS22981 Datasheet, PDF (1/19 Pages) Texas Instruments – 3.3V to 18V Thunderbolt Power Mux

TPS22981
www.ti.com
SLVSBM6 – DECEMBER 2012
3.3V to 18V Thunderbolt Power Mux
Check for Samples: TPS22981
FEATURES
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• Powered from 3.3V
• 4.5V to 19.8V High Voltage Switch
• 3V to 3.6V Switch
• Adjustable Current Limit
• Thermal Shutdown
• Make Before Break Switch
• High Voltage Discharge Before Low Voltage
Make
• Reverse Current Blocking
APPLICATIONS
• Notebook Computers
• Desktop Computers
• Power Management Systems
connector
DC/DC
ENHVU
S0
V3P3OUT
V3P3
ISET_S0
ISET_S3
Exposed Pad ^ISET_V3P3
VHV
R_{SET_S0}
R_{SET_S3}
R_{SET_V3P3}
V3P3
VHV
DC/DC
DESCRIPTION
The TPS22981 is a current-limited power mux
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.
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.
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.
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.
The TPS22981 is available in a 4mm x 4mm x 1mm
QFN package.
µC
Figure 1. Typical Application
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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