Small 2.25 MHz Low-Power DC/DC Converters
Texas Instruments introduced miniature 2.25 MHz, step-down DC/DC converters, which support low-power DSPs and microcontroller-based portable electronics. Said to extend battery life in Bluetooth headsets, cell phones and other Li-Ion battery-powered applications, the converters also save board space. These 300 mA, 600 mA and 1A synchronous, step-down DC/DC converters can efficiently regulate output voltages down to 0.6V with ±1.5 percent accuracy. The TPS62290 provides up to 1A of output current, and it can be powered by a single-cell lithium-ion (Li-Ion), three-cell nickel metal hydride (NiMH) and three-cell alkaline batteries with an input voltage range of 2.3V to 6V. The converter, which operates at a low 15 µA quiescent current, enters a power save mode during light load operating conditions and maintains efficiency up to 95 percent over the entire load current range. For low-noise applications, the device can be forced into fixed frequency pulse width modulation (PWM) mode by pulling the MODE pin high. In the shutdown mode, the TPS62290’s current consumption is reduced to <1 µA. The company also introduced the TPS62260, which supports up to 600 mA of output current, and the TPS62240 to support up to 300 mA. Both devices can support a slightly wider input voltage range of 2V to 6V.