The LM5175EVM-HD high power density evaluation module (EVM) is a 4-switch synchronous buck-boost DC/DC regulator that employs synchronous rectification to achieve extremely high conversion efficiency in a small footprint at 72W output power. Operating over a wide input voltage range of 5.5V to 42V, the output voltage is adjustable from the nominal 12V using only a single resistor or voltage source, permitting the user to customize the output voltage from 0.8V to 24V as needed. Such user configurability is especially useful when traditional DC/DC converters cannot meet system requirements for operating input and output voltage ranges, efficiency, power density, or volume. More specifically, the LM5175EVM-HD is ideal for applications where the input voltage is expected to vary continuously above, equal to, or below the regulated output voltage setpoint in buck, buck-boost, and boost operating modes respectively.
The module design uses the LM5175 high performance, synchronous buck-boost controller with current-mode PWM control loop and adaptive slope compensation, integrated high-side and low-side MOSFET gate drivers, cycle-by cycle overcurrent protection, and precision enable. The EVM's output voltage has better than 1.5% setpoint accuracy. The switching frequency is 400kHz and is synchronizable to a higher frequency if required. Moreover, a dither function provides a smoother EMI signature for noise-sensitive applications. Input UVLO protects the module at low input voltage conditions, and it is possible to tailor the minimum operating input voltage to the application requirements by suitable adjustment of the programmable input UVLO components.
An Excel-based quick-start calculator is available, particularly for guidance with powertrain and compensation circuit component selection.