LMR60440

The LMR60440 is a 3V to 36V (42V transient), 4A synchronous buck converter designed for industrial applications. The LMR60440 offers variants with spread spectrum in an ultra-compact, 2.5mm × 2mm, HotRod QFN-9 package, which reduces inductance and achieves low electromagnetic interference (EMI) performance to facilitate qualification of industrial and other noise-sensitive designs. All device variants are capable of output voltages ranging from 1V to 20V by including a resistor divider between the output voltage node, feedback, and ground. Each variant of the device is also capable of delivering a fixed output voltage by connecting the output voltage node directly to the feedback pin. The Device Comparison Table provides details on the fixed output voltage options. The current-mode control architecture with 40ns minimum on-time allows high conversion ratios at high frequencies, easy loop compensation, fast transient response, and excellent load and line regulation. An open drain power-good output facilitates power sequencing requirements. The MODE/SYNC pin of the LMR60440 allows the user to select between modes of operation. Forced pulse width modulation (FPWM) mode results in constant switching frequency across load while auto mode allows for seamless transitions between pulse width modulation (PWM) and pulse frequency modulation (PFM) switching. In auto mode, the LMR60440 consumes only 5µA of quiescent current, which makes sure of high efficiency at all loads. Few external components are needed allowing for compact PCB layout. The LMR60440 is a part of a family of pin compatible devices ranging in current levels from 0.6A to 6A.