Summit Introduces 10A Synchronous DC-DC Controller With Digital Power Control In Tiny Packages
Summit Microelectronics has expanded its family of Programmable Power Manager (PPM) integrated circuits (ICs) with the SMB211 single-channel, synchronous dc-dc controller. The SMB211 continues Summit’s approach to power supply design by combining flexibility, features and performance with ease-of-use.
With a serial digital interface, the SMB211 can be easily configured during development (on-board, non-volatile memory) and re-programmed in system by host software. According to Summit, the result is a high-performance digitally controlled power supply design that is easily customizable without tedious hardware design cycles or complex microcontroller-style software coding.
The SMB211 combines high-performance power conversion and digital control in a single, space-saving device. The integration of advanced power control functions is said to eliminate external components and cost, improves functionality and performance, and minimizes development time. Summit’s non-volatile configurable technology enables the implementation of flexible "platform solutions" that can be easily modified for different designs without any hardware changes.
"Summit is expanding its portfolio of intelligent dc-dc controllers to address the industry’s increasing demands for high performance, ease-of-use, and reduced Bill of Materials, size and cost. The SMB211’s efficient operation combined with its sophisticated power control enable complex system designs to meet Energy Star™ and other energy-saving standards," stated George Paparrizos, Summit Marketing Director.
The SMB211 integrates a synchronous dc-dc step-down (buck) converter with a useful set of digital control functions. The device’s high current drive capability allows over 10A of output, while using a wide variety of industry-standard MOSFETs. The SMB211 can operate at four different, programmable frequencies (250kHz, 500kHz, 750kHz and 1MHz) allowing optimization of efficiency and component size. Soft-start and power-on delays are also selectable to address various system requirements, especially in multi-power supply applications.
The SMB211’s output voltage accuracy is better than +/- 1% and supports dynamic voltage scaling as well as margin high/low control via the serial digital interface. The output voltage can be digitally set from +0.5 to +2.5V in 10mV steps, or from +1.0 to +5.0V in 20mV steps. The output voltage is monitored for both over- and under-voltage conditions, thereby increasing system reliability. A configurable logic output that can be used as a RESET, POWER GOOD or SMBAlert output signal, is also available for notifying the system of out-of-regulation conditions. The device can operate in forced-PWM for noise-sensitive applications, as well as in automatic PWM/PFM mode for maximum light-load efficiency.
The SMB211 incorporates a pulse-by-pulse current limit by monitoring the voltage drop across the upper N-FET. Various current limit thresholds as well as several over-current response modes are available for maximum design flexibility. An Enable input allows the SMB211 to enter a low-power shutdown mode (less than10uA). A standby mode, via an I2C command, is also available for reducing current consumption while keeping the serial interface active. Additionally, the SMB211 provides complete power system diagnostics by digitally flagging a variety of fault conditions (output OVLO, output UVLO, IC temperature, over-current, input UVLO and others).
The SMB211 operates directly from an input voltage of +4.5 to +13.5V, however the external FETs can be powered from a lower voltage supply, as low as 3.3V, if necessary. The rated operating temperature range is -30C to +85C. Programming is achieved via an industry-standard serial interface and configuration data is safely stored in non-volatile OTP memory.
The SMB211 is well suited for increasingly complex consumer, computing and infrastructure electronics applications such as printers, RAID cards, ADSL/Cable modems/routers, servers, switches/routers, digital televisions, digital set-top boxes (STB) and digital video recorders (DVRs).
The SMB211 is offered in a thermally-enhanced, lead-free 4 x 4mm, 24-pad QFN. Available now in production quantities, the SMB211 is priced at $0.66 each for the QFN package in quantities of 10,000 units.
