The LMR664x0 is a wide input, low-quiescent current, high-performance regulator that can operate over a wide range of duty ratio and the switching frequencies, including sub-AM band at 400 kHz and above AM band at 2.2 MHz. During wide input transients, if the minimum on time or the minimum off time cannot support the desired duty ratio at the higher switching frequency settings, the switching frequency is reduced automatically, allowing the device to maintain the output voltage regulation. With an internally compensated design optimized for minimal output capacitors, the system design process with the device is simplified significantly compared to other buck regulators available in the market.

The device is designed to minimize external component cost and design size while operating in all demanding industrial environments. The device family includes variants that can be set up to operate over a wide switching frequency range, from 200 kHz to 2.2 MHz, with the correct resistor selection from the RT pin to ground. To further reduce system cost, the PG output feature with built-in delayed release allows the elimination of the reset supervisor in many applications.

The LMR664x0 family is designed to reduce EMI/EMC emissions by introducing a dual random spread spectrum (DRSS) switching frequency dithering scheme, using the enhanced HotRod QFN package where no bond wires are used. Also, available is the MODE/SYNC feature that allows synchronization to an external clock. Together, these features reduce the need for any common-mode choke or shielding or any elaborate input filter design scheme, greatly reducing the complexity and cost of the EMI/EMC mitigation measures.

The device comes in an ultra-small, 2.6-mm × 2.6-mm, enhanced, HotRod QFN package allowing for quick optical inspection along with specially designed corner anchor pins for reliable board level solder connections.