SLUAAX7 August   2024 BQ25758

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Derivation
  6. 3Measured Results
  7. 4Summary
  8. 5References

1 Introduction

Figure 1-1 is a block diagram of the BQ25758 dc/dc regulator.

BQ25758 Typical Application Block DiagramFigure 1-1 BQ25758 Typical Application Block Diagram

The BQ25758’s regulation point is the VO_SNS pin. The converter’s VO_SNS is connected as close as possible to the system load to account for resistance losses. However, if a cable is required to connect the output of the end equipment to the system load, the cable resistance causes a voltage drop from the VO_SNS regulation point to the system load. If the cable resistance and the system load current is always known, or an ADC is available to measure the system load, host software can increase the regulation point as a function of system load to account for the voltage drop. Typically, the system load varies too much or too quickly for the host software to respond. A different method to dynamically compensate for the voltage drop across a known cable resistance is presented in the following section.