Intersil ISL911x高度集成1.2A升降压电源解决方案

发布时间：2011-8-29 12:04 发布者：Liming

Intersil公司的ISL9110和ISL9112是高度集成升降压开关稳压电源,输入电压可高于或低于输出电压,并可在降压和升压模式无缝转换,输入电压1.8V-5.5V,输出电流1.2A,效率高达95%,静态电流35uA,开关频率2.5MHz,I2C接口,主要应用在单个锂电池的3.3V稳压器,智能手机和平板电脑,手持设备和POL稳压器.本文介绍了ISL9110和ISL9112主要特性, 方框图,几种典型应用电路图,以及ISL9110IRTNZ/IRT7Z/IRTAZ-EVAL1Z评估板主要特性,电路图和相应的材料清单与PCB元件布局图.

The ISL9110 and ISL9112 are highly-integrated Buck-Boost switching regulators that accept input voltages either above or below the regulated output voltage. Unlike other Buck-Boost regulators, these regulators automatically transition between operating modes without significant output disturbance.

Both parts are capable of delivering up to 1.2A output current, and provide excellent efficiency due to their fully synchronous 4-switch architecture. No-load quiescent current of only 35μA also optimizes efficiency under light-load conditions. Forced PWM and/or synchronization to an external clock may also be selected for noise sensitive applications.

The ISL9110 is designed for standalone applications and supports 3.3V and 5V fixed output voltages or variable output voltages with an external resistor divider. Output voltages as low as 1V, or as high as 5.2V are supported using an external resistor divider.

The ISL9112 supports a broader set of programmable features that may be accessed via an I2C bus interface. With a programmable output voltage range of 1.9V to 5V, the ISL9112 is ideal for applications requiring dynamically changing supply voltages. A programmable slew rate can be selected to provide smooth transitions between output voltage settings.

The ISL9110 and ISL9112 require only a single inductor and very few external components. Power supply solution size is minimized by a tiny 3mmx3mm package and a 2.5MHz switching frequency, which further reduces the size of external components.

ISL9110和ISL9112主要特性:

• Accepts Input Voltages Above or Below Regulated Output Voltage

• Automatic and Seamless Transitions Between Buck and Boost Modes

• Input Voltage Range: 1.8V to 5.5V

• Output Current: Up to 1.2A

• High Efficiency: Up to 95%

• 35μA Quiescent Current Maximizes Light-load Efficiency

•2.5MHz Switching Frequency Minimizes External Component Size

•Selectable Forced-PWM Mode and External Synchronization

•I2C Interface (ISL9112)

• Fully Protected for Overcurrent, Over-temperature and Undervoltage

• Small 3mmx3mm TDFN Package

ISL9110和ISL9112应用:

• Regulated 3.3V from a Single Li-Ion Battery

• Smart Phones and Tablet Computers

• Handheld Devices

• Point-of-Load Regulators

图1. ISL9110和ISL9112方框图

图2. ISL9110IRTAZ 典型应用电路图

图3. ISL9112典型应用电路图

图4. ISL9112IRTNZ 典型应用电路图

ISL9110IRTNZ/IRT7Z/IRTAZ-EVAL1Z评估板

评估板主要特性:

• ISL9110IRTAZ high efficiency buck-boost regulator with adjustable output voltage

• Input voltage rating from 1.8V to 5.5V

• Resistor programmable output voltage, set to 3.3V

• 1200mA output current at VIN ≥ 3V and VOUT = 3.3V

• 2.5MHz switching frequency

• Jumper selectable EN (enabled/disabled)

• Jumper selectable MODE (auto-PFM/forced-PWM)

• LED indicators for PG and BAT status outputs

• Connectors, test points and jumpers for easy evaluation