Analog Devices Inc./Maxim Integrated

The MAX8643A high-efficiency switching regulator delivers up to 3A load current at output voltages from 0.6V to (0.9 x VIN). The IC operates from 2.35V to 3.6V, making it ideal for on-board point-of-load and postregulation applications. Total output error is less than ±1% over load, line, and temperature.The MAX8643A features fixed-frequency PWM mode operation with a switching frequency range of 500kHz to 2MHz set by an external resistor. High-frequency operation allows for an all ceramic capacitor design. The high operating frequency also allows for small-size external components.The low-resistance on-chip nMOS switches ensure high efficiency at heavy loads while minimizing critical inductances, making the layout a much simpler task with respect to discrete solutions. Following a simple layout and footprint ensures first-pass success in new designs.The MAX8643A comes with a high-bandwidth (> 14MHz) voltage-error amplifier. The voltage-mode control architecture and the voltage-error amplifier permit a type III compensation scheme to be utilized to achieve maximum loop bandwidth, up to 20% of the switching frequency. High loop bandwidth provides fast transient response, resulting in less required output capacitance and allowing for all-ceramic capacitor designs.The MAX8643A provides two three-state logic inputs to select one of nine preset output voltages. The preset output voltages allow customers to achieve ±1% output-voltage accuracy without using expensive 0.1% resistors. In addition, the output voltage can be set to any customer value by either using two external resistors at the feedback with 0.6V internal reference or applying an external reference voltage to the REFIN input. The MAX8643A offers programmable soft-start time using one capacitor to reduce input inrush current. The MAX8643A is available in a lead-free, 24-pin, 4mm x 4mm thin QFN package.ApplicationsASIC/CPU/DSP Core and I/O VoltagesBase-Station Power SuppliesDDR Power SuppliesPOLsRAID Control Power SuppliesTelecom and Networking Power Supplies

The MAX8646 high-efficiency switching regulator delivers up to 6A load current at output voltages from 0.6V to 0.9 x VIN. The IC operates from 2.35V to 3.6V, making it ideal for on-board point-of-load and postregulation applications. Total output error is less than ±1% over load, line, and temperature ranges.The MAX8646 features fixed-frequency PWM mode operation with a switching frequency range of 500kHz to 2MHz set by an external resistor. High-frequency operation allows for an all-ceramic capacitor design. The high operating frequency also allows for small-size external components.The low-resistance on-chip nMOS switches ensure high efficiency at heavy loads while minimizing critical inductances, making the layout a much simpler task with respect to discrete solutions. Following a simple layout and footprint ensures first-pass success in new designs.The MAX8646 comes with a high bandwidth (> 14MHz) voltage-error amplifier. The voltage-mode control architecture and the voltage-error amplifier permit a type III compensation scheme to be utilized to achieve maximum loop bandwidth, up to 20% of the switching frequency. High loop bandwidth provides fast transient response, resulting in less required output capacitance and allowing for all-ceramic-capacitor designs.The MAX8646 provides two tri-state logic inputs to select one of nine preset output voltages. The preset output voltages allow customers to achieve ±1% output-voltage accuracy without using expensive 0.1% resistors. In addition, the output voltage can be set to any customer value by either using two external resistors at the feedback with 0.6V internal reference or applying an external reference voltage to the REFIN input. The MAX8646 offers programmable soft-start time using one capacitor to reduce input inrush current. The MAX8646 is available in a lead-free, 24-pin, 4mm x 4mm, thin QFN package.ApplicationsASIC/CPU/DSP Core and I/O VoltagesBase-Station Power SuppliesDDR Power SuppliesPOLsRAID Control Power SuppliesTelecom and Networking Power Supplies

The MAX8647/MAX8648 drive up to six white LEDs or two sets of RGB LEDs with regulated constant current for display backlight and fun light applications. By utilizing an inverting charge pump and extremely low-dropout adaptive current regulators, these ICs achieve very high efficiency over the full 1-cell Li+ battery voltage range and even with large LED forward voltage mismatch. The 1MHz fixed-frequency switching allows for tiny external components. The regulation scheme is optimized to ensure low EMI and low input ripple. The MAX8647/MAX8648 include thermal shutdown, open- and short-circuit protection.The MAX8647 features an I²C serial port, while the MAX8648 features a three-wire serial-pulse logic interface. Both devices support independent on/off and dimming for main and subbacklights. The dimming ranges are pseudo-logarithmic from 24mA to 0.1mA and off in 32 steps. Both devices include a temperature derating function to safely allow bright 24mA full-scale output current setting while automatically reducing current to protect LEDs at high ambient temperatures above +60°C.The MAX8647/MAX8648 are available in a 16-pin,3mm x 3mmthin QFN package (0.8mm max height).ApplicationsCamera Flash or RGB IndicatorsCellular Phones and SmartphonesPDAs, Digital Cameras, and CamcordersWhite LED Backlighting, Single or Dual DisplayWide-Gamut RGB LED Display Backlighting