Dual 3-A and single 6-A programmable integrated buck regulators deliver flexible, high-efficiency power

February 23, 2012 // By Paul Buckley
Summit Microelectronics has expanded the company’s family of programmable DC-DC integrated circuits with the SMB206A and SMB210A. The new products bring cost-effective digital power control to high-volume digital consumer systems as well as general purpose applications.

Like the entire SMB20X family, the SMB206A and SMB210A support advanced power management for ‘green’ and ENERGY STAR applications. These include a wide range of multimedia consumer and broadband/SoHo applications such as digital LCD/LED/plasma/IP televisions, digital cable/satellite/IP set-top boxes and media gateways, broadband cable/DSL modems, wireless SoHo routers and switches.

The SMB206A/SMB210A are dual/single-output integrated DC-DC buck regulators combining Summit’s digital programmability with dense integration, ultra-compact size, and cost-effective bill-of-materials (BoM) necessary for mass-market consumer products.  With a serial digital interface and on-board non-volatile memory, the SMB20X family can be easily configured during development and re-programmed in system by host software. The result is a flexible, digitally controlled power supply design that is easily customizable without tedious hardware design cycles or complex microcontroller-style GPIO-based control.  They can also be programmed by fixed resistors and purchased as standard products with fixed voltages. The integration of advanced power control functions eliminates external components and cost, improves functionality and performance, and minimizes development time.

The SMB206A and SMB210A integrate single or dual step-down DC-DC buck regulators with on-board MOSFET(s) supplying up dual 3 A+3 A (SMB206A), or single 6 A (SMB210A) output currents.  Input voltage range is +4.5 V to +16 V and output voltage range is +0.8 V to VIN, accurate to 2.5% over load/line/temperature.  Output voltage is digitally programmable in ~10 mV steps while other custom voltages are supported with external resistors .  Switching frequency is programmable to 500 kHz or 1 MHz with 180 degrees phase interleave for SMB206A.  Light load efficiency is supported by automatic pulse-skipping operation. Integrated frequency compensation and feedback resistors minimize BoM count, cost and design effort.

Output enable, sequencing, softstart and output voltage (UV) monitoring are all programmable as well.  Output voltage monitoring is coupled to ‘PowerGood’ or ‘RESET’ signals with programmable output assignment and output channels can be enabled via the serial I 2 C interface or by the ENABLE pins.  Nominal output voltages