Dallas - Texas Instruments' TPS54350 is the newest addition to the company's SWIFT (switcher with integrated FET technology) family, a 3-amp, nominal 15-watt DC/DC (non-isolated) PWM buck converter suitable for point-of-load applications.
Working from a 4.5- to 20-volt input, the converter is especially useful for powering DSP, FPGA, and microprocessors directly from a mid-voltage bus, versus an additional low-voltage bus. The TPS54350 also finds use in low-power industrial and commercial systems, liquid crystal display (LCD) monitors, hard disk drives, and video graphics cards. Its output voltage is adjustable down to 0.89 volts with one percent accuracy.
The TPS54350 integrates a high-side MOSFET, and a gate driver for an external, optional low-side MOSFET. The power chip features an operating efficiency approaching 90 percent (for 6 volts in, 3.3 volts out at 3 amps and 500 kHz switching). It has peak-current limiting, thermal shutdown, adjustable under-voltage lockout, and internal soft-start circuitry. Its switching frequency can be fixed at 250 kHz or 500 kHz, or it can be adjusted up to 700 kHz to reduce the size of passive components. The converter comes with an interactive software development tool and evaluation module to help designers meet aggressive development cycles. The software is available free through www.power.ti.com/swift, and provides a bill of materials, reference schematic, loop response graphs and an efficiency curve based on the designer's inputs.
The TPS54350, in a 16-pin HTSSOP with PowerPAD for thermal enhancement and space savings, is priced at $2.45 each in 1k quantities. Fixed-output versions will be available in 1Q 2004.