New buck/boost controller with integrated buck MOSFET for automotive applications
Allegro MicroSystems Europe has introduced a new automotive AEC-Q100 qualified power management IC. The A4450 can implement either a buck or buck/boost regulator to efficiently convert automotive battery voltages into a tightly regulated voltage, with seamless transition between the buck and boost modes. This new device is targeted at the automotive, industrial and instrumentation markets with end applications to include infotainment, instrument clusters, telematics, amplifiers, and control modules.
The device is ideal for automotive input environments where battery input voltage supply can vary above and below the required output voltage and a single inductor/single-stage conversion is desired. The wide input operating voltage range of 3V to 36V makes the device suitable for a range of automotive infotainment applications and handles idle stop/start, cold crank, double battery and load dump conditions. The device features a high-voltage battery compatible enable (EN) input to accommodate for switched battery input applications.
It provides regulated output voltage ranging from 3V to 8V with load current of up to 1ADC. The PWM switching frequency range is 250kHz to 2.4MHz, and frequency dithering and controlled switching transitions minimise EMI. The device maintains excellent stability even when the input and output voltages are at nearly the same level as well as through line and load transient events.
Protection features include pulse-by-pulse current limit, hiccup mode short-circuit protection, LX short-circuit protection, missing freewheeling diode. The enable input is compatible to a high-voltage battery level, and a power-on reset output (NPOR) is integrated.
The device is available in a 20-lead, 4mm x 4mm QFN package (suffix ‘ES’), which is ‘wettable flank’ and AEC-Q100 qualified.