Maxim MAX77831 18W高效降压升压转换器解决方案

Maxim公司的MAX77831是2.5V到16V输入18W输出高效降压/升压转换器.采用内部反馈电阻时,器件默认输出电压为5V,采用外接反馈电阻时可配置成3V至此5V间的任何输出电压.输出电压可通过I2C串口动态进行调整.MAX77831工作在强迫PWM(FPWM)模式.器件默认开关频率为1.8MHz,通过I2C接口可选择为1.5MHz和1.2MHz.器件的保护特性有欠压锁住(UVLO),过流保护(OCP),过压保护(OVP)和热关断(THS).器件采用 2.86mm x 2.06mm 35引脚WLP封装.主要用在高达16V输入的非电池供电应用和具有EN控制的高达16V输入的电池供电的应用.本文介绍了MAX77831主要优势和特性,简化框图,功能框图,典型应用电路图和评估板MAX77831 EVK主要特性和指标,电路图,材料清单和PCB设计图.

The MAX77831 is a high-efficiency, high-performancebuck-boost converter targeted for systems requiring wideinput voltage range (2.5V to 16V). It can supply 18W ofcontinuous output power (for example, up to 2A at 9V (VIN≥ 4V)).

The IC is available in 5V default output voltage when usinginternal feedback resistors. The IC can also be configuredto any default output voltages between 3V and 15Vwhen using external feedback resistors. The output voltageis adjustable dynamically through the I2C serial interface(see the Output Voltage Configuration section). TheIC only operates in forced-PWM (FPWM) mode.

The SEL pin allows a single external resistor to programfour different I2C interface slave addresses, four differentswitching-current limit thresholds, and selection betweenexternal/internal feedback resistors. The different switching-current limit thresholds allow the use of lower profileand smaller external components that are optimized for aparticular application. The use of external feedback resistorsallows for a wider output voltage range and customizableoutput voltages at startup.

An optional I2C serial interface allows dynamically controllingthe output voltage, slew rate of the output voltagechange, switching-current limit threshold, and switchingfrequency. The I2C-programmed settings have priorityover the RSEL decoded settings.