SLVSBX9A September   2014  – September 2014 TPS61291


  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Handling Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Bypass / Boost Mode Operation EN/BYP
      2. 7.3.2 Output Voltage Selection VSEL
      3. 7.3.3 Feedback Divider Disconnect
      4. 7.3.4 Undervoltage Lockout
      5. 7.3.5 Overtemperature Protection
      6. 7.3.6 Overvoltage Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Boost Mode Operation
      2. 7.4.2 Bypass Mode Operation
      3. 7.4.3 Controlled Transition into Bypass Mode
      4. 7.4.4 Operation at Output Overload
      5. 7.4.5 Startup
  8. Applications and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. Inductor Selection
        2. Input and Output Capacitor Selection
      3. 8.2.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

1 Features

  • Input Voltage Range 0.9V to 5V
  • Startup Voltage 1.5V at 20mA Load
  • Pin Selectable Output Voltages: 3.3V, 3V, 2.5V
  • 15nA typical Quiescent Current in Bypass Mode
  • 5.7μA typical Quiescent Current in Boost Mode
  • Bypass Switch from VIN to VOUT
  • IOUT > 200mA at 3.3V VOUT, VIN = 1.8V
  • Internal Feedback Divider Disconnect (Bypass Mode)
  • Controlled Bypass Transition Prevents Reverse Current into Battery
  • Power-Save Mode at Light Loads
  • Overtemperature Protection
  • Redundant Overvoltage Protection
  • Small 2mm x 2mm SON 6-pin package

2 Applications

  • Metering (Gas, Water, Smart Meters)
  • Remote Controls
  • Home Security / Home Automation
  • Single 3V Li-MnO2 or 2 x 1.5V Alkaline Cell Powered Applications

3 Description

The TPS61291 is a boost converter with pin selectable output voltages and an integrated bypass mode. In bypass operation, the device provides a direct path from the input to the system and allows a low power micro controller (MCU) such as the MSP430 to operate directly from a single 3V Li-MnO2 battery or dual alkaline battery cells.

In bypass mode the integrated feedback divider network for boost mode operation is disconnected from the output and the quiescent current consumption drops down to only 15nA (typical).

In boost mode the device provides a minimum output current of 200mA at 3.3V VOUT from 1.8V VIN. The boost mode is used for system components which require a regulated supply voltage and cannot directly operate from the input source. The boost converter is based on a current-mode controller using synchronous rectification to obtain maximum efficiency and consumes typically 5.7uA from the output. During startup of the boost converter, the VSEL pin is read out and the integrated feedback network sets the output voltage to 2.5V, 3V or 3.3V.

Bypass mode or boost mode operation is controlled by the system via the EN/BYP pin.

The device integrates an enhanced bypass mode control to prevent charge, stored in the output capacitor during boost mode operation, from flowing back to the input and charging the battery.

The device is packaged in a small 6-pin SON package (DRV) measuring 2.0mm × 2.0mm x 0.75mm.

Device Information(1)

TPS61291 SON (6) 2.00 mm x 2.00 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.

Simplified Schematic and Efficiency Curves