描述 Description

The AAT1142 SwitchReg is a dynamically programmable 2.2MHz step-down converter with an input voltage range of 2.7V to 5.5V and output from 0.6V to 2.0V. Its low supply current, high level of integration, and small footprint make the AAT1142 the ideal choice for microprocessor core power in systems such as smartphones.
The 2.2MHz switching frequency allows the use of a small external inductor and capacitors. Peak current mode control and internal compensation provide stable operation and fast voltage response without over/undershoot or ringing.
The AAT1142 delivers up to 800mA of output current while consuming 35μA of typical no load quiescent current. Dynamic Voltage Management is provided through I2C or AnalogicTech's S2Cwire? (Simple Serial Control?) single wire interface. The user can program the output from 0.6V to 2.0V in 50mV steps.
The AAT1142 optimizes power efficiency throughout the load range via PWM/PFM mode. Pulling the MODE/SYNC pin high enables PWM Only mode, maintaining constant frequency and low noise across the operating range. Alternatively, the converter may be synchronized to an external clock input via the MODE/SYNC pin. Over-temperature and short-circuit protection safeguard the AAT1142 and system components from damage.
The AAT1142 is available in a Pb-free, space-saving 2.85x3.0x1.0mm TSOPJW-12 package or a Pb-free, low-profile 3x3x0.8mm TDFN33-12 package. The device is rated over the -40°C to +85°C temperature range.

特性 Features

·VIN Range: 2.7V to 5.5V
·Variable Output Voltage: 0.6V to 2.0V
·Dynamic Voltage Management
·50mV Output Resolution
·Fast, Stable Response
·Serial Control Options:
·I2C Two-Wire Interface
·S2Cwire Single-Wire Interface
·800mA Output Current
·Up to 93% Efficiency
·Load/Line Regulation Less Than ±0.5%
·2.2MHz Switching Frequency
·Ultra-Small External Filter
·Low 35μA No Load Quiescent Current
·100% Duty Cycle Low Dropout Operation
·Internal Soft Start
·Over-Temperature Protection
·Current Limit Protection
·Multi-Function MODE/SYNC Pin:
·PWM/PFM for High Efficiency
·PWM Only for Low Noise
·Clock Input to Synchronize to System Clock
·Pb-Free TDFN33-12 or TSOPJW-12 Package
·-40°C to +85°C Temperature Range