The MAX1937/MAX1938/MAX1939 comprise a family of synchronous, two-phase, step-down controllers capable of delivering load currents up to 60A. The controllers utilize Quick-PWM™ control architecture in conjunction with active load-current voltage positioning. Quick-PWM control provides instantaneous load-step response, while programmable voltage positioning allows the converter to utilize full transient regulation limits, reducing the output capacitance requirement. The two phases operate 180° out-of-phase with an effective 500kHz switching frequency, thus reducing input and output current ripple, as well as reducing input filter capacitor requirements. The MAX1937/MAX1938/MAX1939 are compliant with AMD Hammer, Intel®‚ Voltage-Regulator Module (VRM) 9.0/9.1, and AMD Athlon™ Mobile VID code specifications (see Table 1 for VID codes). The internal DAC provides ultra-high accuracy of ±0.75%. A controlled VID voltage transition is implemented to minimize both undervoltage and overvoltage overshoot during VID input change. Remote sensing is available for high output-voltage accuracy. The MOSFET switches are driven by a 6V gate-drive circuit to minimize switching and crossover conduction losses to achieve efficiency as high as 90%. The MAX1937/MAX1938/MAX1939 feature cycle-by-cycle current limit to ensure that the current limit is not exceeded. Crowbar protection is available to protect against output overvoltage. Applications * Blade Servers * High-End Switches and Routers * High-End Switches and Routers * Macro Base Stations * Notebook and Desktop Computers * Servers and Workstations * ±0.75% Output Voltage Accuracy * Instant Load-Transient Response * Up to 90% Efficiency Eliminates Heatsinks * Up to 60A Output Current * 8V to 24V Input Range * User-Programmable Voltage Positioning * Controlled VID Voltage Transition * 500kHz Effective Switching Frequency * MAX1937: AMD Hammer Compatible * MAX1938: Intel VRM 9.0/9.1 Compatible * MAX1939: AMD Athlon Mobile Compatible * Soft-Start * Power-Good (PWRGD) Output * Cycle-by-Cycle Current Limit * Output Overvoltage Protection (OVP) * RDS(ON) or RSENSE Current Sensing * Remote Voltage Sensing * 28-Pin QSOP Package