Ams introduces a 200mA ultra-compact high-efficiency boost converter for single lithium battery powered products

     Ams AG, the world's leading supplier of high-performance analog ics and sensors, has introduced an efficient and compact boost converter, the AS1383, that helps extend the uptime of single-battery Li-ion devices. The converter has an input voltage range of 2.7V to 5.5V and an output voltage range of 2.7V to 5.0V. Users can choose either an adjustable voltage version or a factory-pre-programmed fixed voltage version. Depending on the input voltage, the device can provide an output current of up to 200mA.

     The AS1383 uses peak current PWM control mode to achieve accurate line adjustment and load adjustment. The integrated NMOS and PMOS power tubes have extremely low on-impedance and gate capacitance. This helped the converter achieve high conversion efficiency, with peak efficiency of up to 92% in the moderate to full load range.

     In addition, the device has an intelligent power saving mode. When the chip is working at the minimum open time, if the output energy is still higher than the energy consumed by the load, the chip will automatically shut down all the other circuits except the output voltage monitoring circuit. Under light load conditions, the power saving mode reduces power consumption to 25uA.

     The AS1383 can operate at a high fixed switching frequency of 3.5MHz, requiring small input and output capacitors and an inductor of only 1µH. The adjustable voltage version requires two additional resistors to set the output voltage.

     The converter is in a six-pin wafer-level chip package with a board occupancy area of only 1.2mm x 0.8mm and a pin spacing of 0.4mm. This means that AS1383-based circuits will have a very small size and can be used in the design of the latest consumer products such as wristbands, media players, digital cameras and mobile phones.

     The AS1383 uses a fixed switching frequency and integrates an anti-oscillation circuit to help system designers realize the design of low-noise end products. Under a 150mA current load, its output ripple peaks at 20mV. This output ripple is low enough to completely avoid interference with sensitive downlink signals.

     Bernd Krafthoefer, AMS Marketing Manager, said: "The AS1383 enables AMS to achieve the perfect combination of small size solutions and high conversion efficiency in the light to 200mA load range. Oems can use this design to effectively extend the life of their devices per charge, so that they do not need to be recharged frequently to meet consumer demand."