SLVSLZ3 August   2026 TLV612901

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 I2C Interface Timing Requirements
    7. 6.7 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Output Voltage Setting
      2. 7.3.2 Switching Frequency and Spread Spectrum Function
    4. 7.4 Device Functional Modes
      1. 7.4.1  Enable and Start-Up
      2. 7.4.2  Operation Mode Setting
      3. 7.4.3  Bypass Mode
      4. 7.4.4  Boost Control Operation
      5. 7.4.5  Auto PFM Mode
      6. 7.4.6  Forced PWM Mode
      7. 7.4.7  Ultrasonic Mode
      8. 7.4.8  Output Discharge
      9. 7.4.9  Undervoltage Lockout
      10. 7.4.10 Current Limit Operation
      11. 7.4.11 Output Short-to-Ground Protection
      12. 7.4.12 Overvoltage Protection
      13. 7.4.13 Thermal Shutdown
      14. 7.4.14 Power-Good Indication Status
    5. 7.5 Programming
      1. 7.5.1 Data Validity
      2. 7.5.2 START and STOP Conditions
      3. 7.5.3 Byte Format
      4. 7.5.4 Acknowledge (ACK) and Not Acknowledge (NACK)
      5. 7.5.5 Target Address and Data Direction Bit
      6. 7.5.6 Single Read and Write
      7. 7.5.7 Multi-Read and Multi-Write
  9. 8 Register Maps
    1. 8.1 DeviceID Register
    2. 8.2 CONFIG Register
    3. 8.3 VOUTFLOORSET Register
    4. 8.4 ILIMBSTSET Register
    5. 8.5 VOUTROOFSET Register
    6. 8.6 STATUS Register
    7. 8.7 ILIMPTSET Register
    8. 8.8 BSTLOOP Register
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 TLV612901 With 2.5V – 4.85V VIN, 5.0V VOUT, 3A Output Current
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Inductor Selection
          2. 9.2.1.2.2 Output Capacitor
          3. 9.2.1.2.3 Input Capacitor
          4. 9.2.1.2.4 Checking Loop Stability
        3. 9.2.1.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
      3. 9.4.3 Thermal Information
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information
    1.     79

7.4.3 Bypass Mode

The TLV612901 contains an internal switch for bypassing the DC/DC boost converter during bypass mode. When the input voltage is larger than the preset output voltage, the converter seamlessly transitions into 0% duty cycle operation and the bypass FET is fully turned on.

In auto PFM mode, entry in auto bypass mode is triggered by condition where VOUT > (1 + 0.5%) × VOUT_TAR and VIN > VOUT – 20mV.

In forced PWM mode, the device enters bypass mode when both of the following conditions are met:

  • VOUT > (1 + 2%) × VOUT_TAR.
  • Seven consecutive cycles of maximum clamped off-time occurs (typical tOFF is 2.25μs of each cycle and total 16μs).
Auto bypass mode exit is triggered by bypass current limit or VOUT < (1 – 3%) × VOUT_TAR.

When ENABLE bit (CONFIG[5:6]) = 10, the device is configured in forced bypass mode. The device enters forced bypass mode when VIN > VOUT + 30mV. And forced bypass mode exit is triggered by the bypass current limit.

In bypass mode, the load (RF PA for instance) is directly supplied from the battery for maximum output power, highest efficiency and lowest possible input-to-output voltage difference. The device consumes only a standby current of 35µA (typical). In bypass mode, the device is protected from short-circuit by a very fast current limit detection scheme.

During this operation, the output voltage follows the input voltage. In bypass mode, due to the presence of the bypass MOSFET, the output voltage drop depends on the input voltage, the RDSON of the bypass MOSFET, and the output current. Use the following equation to calculate the output voltage:

Equation 4. VOUT=VIN-RDSON(BP)×IOUT

Conversely, the folloqing equation gives the efficiency in bypass mode:

Equation 5. η=1-RDSON(BP)IOUTVIN
  • RDSON(BP) is the typical on-resistance of the bypass FET

During bypass mode, the TLV612901 device has overcurrent and short-circuit protection by a fast current limit detection scheme. If the current in the bypass FET exceeds approximately 8A (programmable through I2C), the bypass FET is turned off, then the TLV612901 enters into output short-to-ground protection mode. After the overcurrent or short-circuit is released, the TLV612901 goes through the start-up procedure again.