MAXIM MAX1718EEI-TG068

The MAX1718 step-down controller is intended for core CPU DC-DC converters in notebook computers. It features a dynamically adjustable output, ultra-fast transient response, high DC accuracy, and high efficiency needed for leading-edge CPU core power supplies. Maxim’s proprietary Quick-PWM™ quick-response, constant-ontime PWM control scheme handles wide input/output voltage ratios with ease and provides 100ns “instant-on” response to load transients while maintaining a relatively constant switching frequency.

• The MAX1718 step-down controller features a dynamically adjustable output, ultra-fast transient response, high DC accuracy, and high efficiency needed for leading-edge CPU core power supplies.
• Maxim’s proprietary Quick-PWM™ quick-response, constant-ontime PWM control scheme handles wide input/output voltage ratios with ease and provides 100ns “instant-on” response to load transients while maintaining a relatively constant switching frequency.
• The output voltage can be dynamically adjusted through the 5-bit digital-to-analog converter (DAC) over a 0.6V to 1.75V range.
• The MAX1718 has an internal multiplexer that accepts three unique 5-bit VID DAC codes corresponding to Performance, Battery, and Suspend modes.
• Precision slew-rate control provides “just-in-time” arrival at the new DAC setting, minimizing surge currents to and from the battery.
• The internal DAC of the MAX1718B is synchronized to the slew-rate clock for improved operation under aggressive power management of newer chipsets and operating systems that can make incomplete mode transitions.
• A pair of complementary offset control inputs allows easy compensation for IR drops in PC board traces or creation of a voltage-positioned power supply.
• Voltagepositioning modifies the load-transient response to reduce output capacitor requirements and total system power dissipation.
• Single-stage buck conversion allows these devices to directly step down high-voltage batteries for the highest possible efficiency.
• Alternatively, two-stage conversion (stepping down the 5V system supply instead of the battery) at a higher switching frequency allows the minimum possible physical size.
• The MAX1718 is available in a 28-pin QSOP package.
• Quick-PWM Architecture
• ±1% VOUT Accuracy Over Line and Load
• 5-Bit On-Board DAC with Input Muxes
• Precision-Adjustable VOUT Slew Control
• 0.6V to 1.75V Output Adjust Range
• Precision Offset Control
• Supports Voltage-Positioned Applications
• 2V to 28V Battery Input Range
• Requires a Separate 5V Bias Supply
• 200/300/550/1000kHz Switching Frequency
• Over/Undervoltage Protection
• Drives Large Synchronous-Rectifier FETs
• 700μA (typ) ICC Supply Current
• (typ) Shutdown Supply Current
• 2.7±1% Reference Output
• VGATE Blanking During Transition
• Small 28-Pin QSOP Package

• IMVP-II Notebook Computers
• 2-Cell to 4-Cell Li+ Battery to CPU Core Supply Converters
• 5V to CPU Core Supply Converters