SLUU180B January   2022  – February 2022 TPS40070 , TPS40071

 

  1.   Trademarks
  2. 1Introduction
  3. 2Description
  4. 3Schematic
    1. 3.1 Output Filter Components
    2. 3.2 MOSFET Selection
    3. 3.3 Frequency Feedforward Resistor Selection
    4. 3.4 Output Voltage Setpoint
    5. 3.5 Short Circuit Protection Resistor Selection
    6. 3.6 Miscellaneous Parts
    7. 3.7 Control Loop Compensation
  5. 4Test Setup
  6. 5Results
    1. 5.1 Control Loop Characteristics
  7. 6Assembly Drawing and PCB Layout
  8. 7List of Materials
  9. 8Reference
  10. 9Revision History

2 Description

The TPS40070/TPS40071 synchronous buck controller family offers a variety of user-programmable functions including the following:

  • Switching frequency
  • Soft start
  • High-side current limit
  • UVLO
  • External compensation

The controller operates with fixed frequency voltage mode control with an input voltage feedforward control input, which improves performance in applications that have a variable input source. The TPS40071 is selected in the EVM because it operates in source-sink mode over the entire operating range.

The TPS40071 incorporates internal gate drivers for external N-channel MOSFETs in the high-side switch and low-side synchronous rectifier locations. The MOSFET drivers utilize TI’s proprietary Predictive Gate Drive technique, which works to minimize the body diode conduction interval to reduce undesired power loss. The PowerPAD™ package allows the regulator bias power and the gate drive power to be safely dissipated without raising the junction an excessive amount. The high-side current limit/short circuit protection senses the voltage drop across the top-side MOSFET and compares it to a programmable reference to terminate output pulses on a pulse by pulse basis.

The TPS40071EVM−001 highlights the small size, highly efficient solutions that can be attained using theTPS40071 controller. This user guide provides the collateral necessary to evaluate the TPS40071 in a typical application. The collateral includes the following:

  • Schematic
  • List of materials
  • Test setup
  • Assembly drawings
  • PCB layout

The TPS40071EVM−001 offers the following performance features:

  • Operates continuously over a 4.75-V to 14-V input range
  • Delivers 1.8-V output at 10 A; configurable for other voltages
  • Excellent line/load regulation – better than 0.1%
  • 96% efficient with VIN = 8 V, VOUT = 3.3 V
  • Power-good signal
  • Output short circuit protection