TIDT324 February   2023

 

  1.   Description
  2.   Features
  3.   Applications
  4. 1Test Prerequisites
    1. 1.1 Voltage and Current Requirements
    2. 1.2 Required Equipment
    3. 1.3 Considerations
  5. 2Testing and Results
    1. 2.1 Efficiency Graphs
    2. 2.2 Efficiency Data
    3. 2.3 Thermal Images
    4. 2.4 Dimensions
  6. 3Waveforms
    1. 3.1 Switching
    2. 3.2 Output Voltage Ripple
    3. 3.3 Load Transient
    4. 3.4 Start-Up

1.3 Considerations

All voltage measurements were made relative to the 0-V common GND. When taking measurements, make sure to connect the GND clips of the oscilloscope to the GND (that is, 0-V) connection. Do not connect the oscilloscope GND clips to the –VOUT node. Though this –VOUT is the reference for the GND pins of the regulator IC, the output is no longer considered 0-V common GND.

In the inverting buck-boost topology, the voltage potential between the VIN and GND pins of the converter or regulator is the sum of the magnitudes of VIN and VOUT voltages. For example, with a nominal input voltage of +12 V, the total voltage potential exhibited by the LM61495 is: |+12 V| + |–8 V| = 20 V. The LM61495 has a maximum recommended supply voltage of 36 V. Therefore, do not apply an input voltage greater than 28 VIN to the converter, preferably lower, to provide an extra buffer to accommodate for switching voltage spikes.