原标题：Intersil ISL9305H 3MHz微处理器电源解决方案

　　Intersil公司的ISL9305H是密你电源管理IC(mini-PMIC), 集成了两个高效的3MHz同步降压转换器(DCD1和DCD2)以及两个低输入低压降的线路稳压器(LDO1 和LDO2), DCD1和DCD2可提供1.5A电流, LDO1和LDO2可提供300A电流,主要用于手机和智能手机,PDA,PMP和手持仪表,DSP内核电源以及用单节锂电池电源的设备.本文介绍了 ISL9305H主要特性,方框图, 典型应用电路图以及ISL9305IRTZEVAL1Z评估板电路图,材料清单与PCB布局图.

　　ISL9305H is an integrated mini Power Management IC (mini-PMIC) for powering low-voltage microprocessor, or applications using a single Li-Ion or Li-Polymer cell battery to power multiple voltage rails. ISL9305H integrates two high-efficiency 3MHz synchronous step-down converters (DCD1 and DCD2) and two low-input, low-dropout linear regulators (LDO1 and LDO2).

　　The 3MHz PWM switching frequency allows the use of very small external inductors and apacitors. Both step-down converters can enter skip mode under light load conditions to further improve the efficiency and maximize the battery life.

　　For noise sensitive applications, they can also be programmed through I2C interface to operate in forced PWM mode regardless of the load current condition. The I2C interface supports on-the-fly slew rate control of the output voltage from 0.825V to 3.6V at 25mV/step size for dynamic power saving.

　　Each step-down converter can supply up to 1.5A load current. The default output voltage can be set from 0.8V to VIN using external feedback resistors on the adjustable version, or the ISL9305H can be ordered in factory pre-set power-up default voltages in increments of 100mV from 0.9V to 3.6V.

　　ISL9305H also provides two 300mA low dropout (LDO) regulators. The input voltage range is 1.5V to 5.5V allowing them to be powered from one of the on-chip step-down converters or directly from the battery. The default LDO output comes with factory pre-set fixed output voltage options between 0.9V to 3.3V. ISL9305H is available in a 4mmx4mm 16 Ld TQFN package.

　　ISL9305H主要特性:

　　• Dual 1.5A, Synchronous Step-down Converters and Dual 300mA, General-purpose LDOs

　　• Input Voltage Range

　　- DCD1/DCD2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5V to 5.5V

　　- LDO1/LDO2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5V to 5.5V

　　• 400kb/s I2C-Bus Series Interface Transfers the Control Data Between the Host Controller and the ISL9305H

　　• Adjustable Output Voltage

　　- DCD1/DCD2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.8V to VIN

　　- Fixed Output I2C Programmability

　　• At 25mV/Step . . . . . . . . . . . . . . . . . . . . . . . . . .0.825V to 3.6V

　　• LDO1/LDO2 Output Voltage I2C Programmability

　　- At 50mV/Step . . . . . . . . . . . . . . . . . . . . . . . . . . 0.9V to 3.3V

　　• 50μA IQ (Typ) with DCD1/DCD2 in Skip Mode; 20μA IQ (Typ) for Each Enabled LDO

　　• On-the-fly I2C Programming of DC/DC and LDO Output Voltages

　　• DCD1/DCD2 I2C Programmable Skip Mode Under Light Load or Forced Fixed Switching Frequency PWM Mode

　　• Small, Thin 4mmx4mm TQFN Package

　　ISL9305H应用:

　　• Cellular Phones, Smart Phones

　　• PDAs, Portable Media Players, Portable Instruments

　　• Single Li-Ion/Li-Polymer Battery-Powered Equipment

　　• DSP Core Power

　　图1.ISL9305H方框图

　　图2.ISL9305H典型应用电路图

　　ISL9305IRTZEVAL1Z 和ISL9305HIRTZEVAL1Z评估板

　　• Input voltage rating from 2.3V to 5.5V

　　• Two 800mA buck converters for ISL9305 and two 1.5A buck converters for ISL9305H

　　• Two 300mA LDOs

　　• Output voltages are programmable with I2C

　　• 3MHz switching frequency

　　• Connector, test point and Jumper

　　ISL9305HIRTZEVAL1Z评估板材料清单:

　　图.ISL9305HIRTZEVAL1Z评估板PCB布局图