Buck-boost DC/DC converter extends battery life
A buck-boost DC/DC converter with built-in MOSFET is claimed to have the lowest current consumption in the industry. The BU33UV7NUX is suitable for electronic devices powered by batteries, such as electronic dictionaries, remote controls for home appliances, and toys, says Rohm Semiconductor.
The BU33UV7NUX converter outputs the 3.3V necessary for driving MCUs in applications requiring 1.0 to 3.0V input from one to two batteries. The low current consumption of seven microA (vs functionally equivalent products) enables the converter to extend the operating time compared to conventional products, from 540 days to 715 days, says the company, based on 50 microA load current and assuming standby operation in conventional remote controls driven by two alkaline batteries. An integral load current mode switching function allows existing remote controls to support the latest high-performance systems equipped with LCD panels, providing greater energy savings in a range of applications.
This makes it possible to increase battery life in conventional remote controls typically powered by two alkaline batteries by approximately 1.3x over existing solutions, adds Rohm. In addition, the BU33UV7NUX can be driven by input voltages as low as 0.9V and supports a variety of battery types including lithium, such as the coin cells commonly used. The built-in battery leak detection function makes it particularly suited for single use battery applications, adds Rohm.
Adopting a low-power mode, pulse frequency modulation (PFM) control, is adopted for 50mA or lower load currents, featuring seven microA current consumption.
The BU33UV7NUX automatically switches to its high-power pulse width modulation (PWM) mode for high-performance (500mA maximum load current, 13 microA current consumption, PFM/PWM switching control), make it possible to achieve high efficiency power conversion as high as 94 per cent under a wide range of conditions, says Rohm.