LKWIC LKM4644B

LKM4644B is a quad-output, independent, non-isolated switch-mode DC/DC power module. It integrates four independent regulator channels, each capable of delivering up to 5A continuous output current with minimal external input and output capacitors. Each regulator channel provides a precisely regulated output voltage from 0.6V to 5.5V over an input voltage range of 4V to 16V, set by a single external resistor. With an external bias voltage, the module can operate from input voltages as low as 3.1V. The module integrates four independent constant-frequency, controlled on-time, valley current mode regulators, power MOSFETs, inductors, and other supporting discrete components. The typical switching frequency is set to 1MHz. For switching-noise-sensitive applications, the micro-module regulator can be externally synchronized to a clock between 700kHz and 1.3MHz. Current mode control with internal feedback loop compensation provides ample stability margin and excellent transient performance, supporting a wide range of output capacitor types, including all-ceramic output capacitors. Current mode control also offers the flexibility to parallel any independent regulator channels with accurate current sharing. With built-in clock interleaving between every two regulator channels, the LKM4644B easily supports 2+2, 3+1, or 4-channel parallel operation, making it highly flexible for multi-rail point-of-load applications such as FPGAs. In addition, the LKM4644B features CLKIN and CLKOUT pins for frequency synchronization or multi-phase, multi-device cascading, allowing up to 8 phases to operate simultaneously. Current mode control also provides fast cycle-by-cycle current monitoring. Foldback current limiting is provided under overcurrent conditions, reducing the inductor valley current to approximately 40% of its original value when VFB drops. If the output feedback voltage deviates from the regulation point beyond a ±10% window, internal overvoltage and undervoltage comparators pull the open-drain PGOOD output low. Forced continuous conduction mode operation is applied under overvoltage and undervoltage conditions, except during startup when the TRACK pin voltage rises to 0.6V. Pulling the RUN pin below 1.1V forces the controller into shutdown, turning off the power MOSFETs and most internal control circuitry. Under light load current, discontinuous conduction mode operation can be enabled by setting the MODE pin to SGND for higher efficiency compared to continuous conduction mode. The TRACK/SS pin is used for power supply tracking and soft-start programming. The module integrates an internal temperature diode for monitoring the module temperature.

• Quad-channel step-down micro-module regulator
• 5A DC output current per channel
• Wide input voltage range: 4V ~ 16V; with SVIN external bias, VIN: 3.1V ~ 16V
• 0.6V ~ 5.5V output voltage
• Power dissipation up to 5.5W (TA=60°C, 200LFM, no heatsink)
• Output voltage accuracy: ±1.5%
• Current mode control, fast transient response
• Parallel multi-channel capability for higher output current
• Output voltage tracking
• Internal temperature monitoring output
• External frequency synchronization
• OVP, OCP, and OTP
• Operating temperature: -40℃ ~ +85℃
• Package: BGA77 (9.00mm × 15.00mm × 2.50mm)

• Multi-rail point-of-load regulation
• FPGA, DSP, and ASIC applications