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SMB122/SMB122X

Eight-Channel Programmable DC-DC Power Managers with Battery Charger FEATURES & APPLICATIONS INTRODUCTION

Digital programming of all major parameters via I
2 C interface and non-volatile memory The SMB122 and SMB122X are highly integrated and flexible eight-channel power managers designed for use in a wide range of portable applications. The built-in digital programmability allows system designers to custom tailor the device to suit almost any multi-channel power supply application from digital camcorders to mobile phones. The SMB122 and SMB122X integrate all the essential blocks required to implement a complete eight-channel power subsystem including three synchronous step-down “Buck” converters, one configurable step-up “Boost” or step-down synchronous “Buck” converter, two step-up (Boost) converters, one configurable step-up “Boost” or inverting step-up/down “Buck-Boost” converter, one linear regulator (LDO) and a fully programmable Li-Ion battery charger. Additionally sophisticated power control/monitoring functions required by complex systems are built-in. These include digitally programmable output voltage setpoint, power-up/down sequencing, enable/disable, margining, dynamic voltage management, and UV/OV input/output monitoring on all channels. By incorporating a second ENABLE input and 7-level dynamic voltage control, the SMB122X is ideal for powering systems based on Xscale™ and other similar processors. The integration of features and built-in flexibility of the SMB122 and SMB122X allows the system designer to create a “platform solution” that can be easily modified via software without major hardware changes. Combined with the re-programmability of the SMB122 and SMB122X, this facilitates rapid design cycles and proliferation from a base design to futures generations of product. The SMB122 and SMB122X are suited to battery-powered applications with an input range of +2.7V to +6.0V and provide a very accurate voltage regulation (<1.5%, typical). Communication is accomplished via the industry standard I o Output voltage setpoint/margining o Sequencing & digital soft start o Enable/Disable outputs independently o Input/Output UV/OV voltage thresholds o PWM/PFM mode Eight programmable regulator channels o Three synchronous step-down (Buck) with internal PFETs o One configurable step-up (Boost) or synchronous step-down (Buck) o Two step-up (Boost) o One configurable step-up (Boost) or inverting step-up/down (Buck-Boost) o One adjustable output voltage LDO Programmable Linear Li-Ion Battery Charger o Precharge/fast charge/termination current o Fast Charge voltage threshold o Float Voltage +2.7V to +6.0V Input Range (Higher system voltages supported) Built-in current limiting, UV/OV, and thermal protection Highly accurate reference and output voltage (<1.5%) 1MHz PWM frequency and automatic power-saving PFM mode 96 bytes of user configurable nonvolatile memory

Applications

Portable Media Players Digital camcorders/still cameras
2 C bus. All user-programmed settings are stored in non-volatile EEPROM of which 96 bytes may be used for general-purpose memory applications. The commercial operating temperature range is 0C to +70C, the industrial operating range is –40C to +85C, and the available package is a 64-pad 9mm x 9mm QFN. Smart PDA/Camera phones Handheld GPS/PDAs Portable Equipment

SIMPLIFIED APPLICATIONS DRAWING

SMB122(SMB122X)

+4.5V to +6.0VDC IN LDO +1.5V to +3.75V MCU/RTC Li-IonCharger Step-Up orInvertingChannel -35V to +35V (Prog.) TFT-LCD/CCD Sensor Li-Ion Batteryor+2.7V to +6.0V Vin to +35V (Prog.) LEDBacklight 2 Step-UpChannels Vin to +35V (Prog.) TFT-LCDBias Step-Up orStep-DownChannel I 2 C/SMBus +0.5V to +35V (Prog.) Memory, I/O (System Enable) SystemControlandMonitoring +0.5V to Vin (Prog.) CPU Core Pushbutton Power Shutdown 3 Step-DownChannels +0.5V to Vin (Prog.) DSP/CODEC Control Inputs Status Outputs +0.5V to Vin (Prog.) Analog/RF Figure 1 – Applications block diagram featuring the SMB122/X eight-channel, programmable DC/DC converters. This integrated power supply and battery manager provides precision regulation, monitoring, cascade sequencing, output margining and battery charging. © SUMMIT Microelectronics, Inc. 2006
757 North Mary Avenue • Sunnyvale CA 94085 • Phone 408 523-1000 • FAX 408 523-1266

1 http://www.summitmicro.com/

2105 3.0 10/8/2008