JAJSV63A August 2024 – August 2024 LM5137-Q1
ADVANCE INFORMATION
Configure the dual outputs for fixed 5V and 3.3V voltage setpoints by tying the respective FB pins to VDDA through 24.9kΩ and 7.5kΩ resistors, respectively.
Alternatively, use feedback resistor dividers values for 5V and 3.3V output voltage setpoints based on the 0.8V feedback reference of the LM5137-Q1. Calculate the upper feedback resistors using Equation 41 assuming a value of 15kΩ for the lower resistors.
Equation 40 calculates the resultant output voltage setpoints when using 78.7kΩ, 47kΩ and 15kΩ standard E192 0.5% resistor values.
In contrast to a fixed output option, installing a feedback resistor divider with a suitable series resistor, typically 50Ω, facilitates measurement of the loop gain characteristic as needed to characterize stability.