Maxim Integrated Products’ new MAX1540/MAX1541 dual, pulse-width modulation (PWM) step-down controllers provide high efficiency, excellent transient response, and high dc-output accuracy. These devices are ideal for stepping down high-voltage batteries to generate low-voltage chipset and RAM power supplies in notebook computers.
These Quick-PWM™ controllers are free running, with constant on-time and input feed-forward. This configuration provides ultrafast transient response, wide input-output differential range, low supply current, and tight load-regulation characteristics. To ensure reliable overload and inductor saturation protection, the MAX1540/MAX1541 accurately sense the inductor current across an external current-sense resistor in series with the output. Alternatively, these controllers can use the synchronous rectifier method or lossless inductor current-sensing method to provide overload protection with lower power dissipation.
The MAX1540 generates chipset, DRAM, CPU I/O, or other low-voltage supplies down to 0.7 V. The MAX1541 powers chipsets and graphics processor cores that require dynamically adjustable output voltages, or generates the active termination bus that tracks the input reference.
The MAX1540 is packaged in a 32-pin thin QFN and the MAX1541 is packaged in a 40-pin thin QFN. Both devices have optional inductor-saturation protection and overvoltage/undervoltage protection. These devices are screened for the extended-industrial temperature range (-40°C to 85°C). For more information, visit www.maxim-ic.com.