Product details


IN1 rDS(on) (Typ) (mOhm) 250 IN2 rDS(on) (Typ) (mOhms) 125 IN1 output current (Max) (A) 3.1 IN2 output current (Max) (A) 3.1 Number of Inputs 2 Rating Catalog Operating temperature range (C) -40 to 85 Approx. price (US$) 0.97 | 1ku open-in-new Find other Power muxes

Package | Pins | Size

VQFN (RGP) 20 16 mm² 4 x 4 open-in-new Find other Power muxes


  • Powered from 3.3 V
  • 4.5-V to 19.8-V High-Voltage Switch
  • 3-V to 3.6-V Switch
  • Adjustable Current Limit
  • Thermal Shutdown
  • Make Before Break Switch
  • High-Voltage Discharge Before Low-Voltage Make
  • Reverse Current Blocking
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The TPS22981 device is a current-limited power mux providing a connection to a peripheral device from either a low-voltage supply (3 V to 3.6 V) or a high-voltage supply (4.5 V to 19.8 V). 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 3.3 V and then make the V3P3 connection. The output may transition to 0 V when a load is present, before returning to 3.3 V.

The TPS22981 is available in a 4 mm × 4 mm × 1 mm VQFN package.

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Technical documentation

= Featured
No results found. Please clear your search and try again. View all 6
Type Title Date
* Datasheet TPS22981 3.3-V to 18-V Thunderbolt™ Power Mux datasheet (Rev. B) Nov. 25, 2015
Technical articles How can a load switch extend your device’s battery life? Mar. 20, 2018
Technical articles How and why you should use load switches for power sequencing Feb. 06, 2018
Technical articles How to use load switches and eFuses in your set-top box design Nov. 23, 2017
Technical articles Don’t leave it floating! Power off your outputs with quick output discharge Dec. 09, 2016
User guides TPS22981EVM User’s Guide Nov. 13, 2012

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Hardware development

document-generic User guide
The Texas Instruments TPS22981EVM evaluation module (EVM) helps designers evaluate the operation and performance of the TPS22981 3.3 V to 18 V MUX with over current limit. The TPS22981 is a current-limited power MUX providing a connection to a peripheral device from either a low voltage supply (3.15 (...)
  • 3.15 V to 3.6 V Low Voltage Switch
  • 5 V to 18 V High Voltage Switch
  • Adjustable Current Limit
  • Thermal Shutdown

Design tools & simulation

SLVM724.ZIP (9 KB) - IBIS Model
SLVM727.ZIP (9 KB) - HSpice Model

CAD/CAE symbols

Package Pins Download
QFN (RGP) 20 View options

Ordering & quality

Support & training

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What is power muxing?

This video is an introduction to power muxing systems and solutions.

Posted: 26-Jan-2019
Duration: 14:26

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