AK7844

AKEMD AKEMD CONFIDENTIAL [AK7844] www.DataSheet4U.com AK7844 Stereo Audio Class-D Amp with Power Booster for Piezo Speakers GENERAL DESCRIPTION THE AK7844 is Stereo Class-D amplifier for driving Piezo-Electric Speakers. Built-in Boost DCDC converter generates adequate high voltage for driving Piezo Speakers from Li-Ion battery. AKM state-of-the-art filter-less solution eliminates LC-filters, which are normally required at Class-D outputs. That contributes to total space saving. Class-D operation ensures higher power efficiency, and couple with Piezo Speaker that is low-powerconsumption and low-profile figure. The AK7844 is very applicable for cellular phones with piezo speakers. FEATURES □ Class-D Amplifier ： Piezo-Electric Speaker Driver Single-ended analog Input BTL output Output voltage = 8Vrms @VDD1=8.75V Filter-less solution Stereo mode Pop noise suppressor Output short protection □ Boost DCDC Converter ： Input voltage (Battery) = 2.7V ∼ 4.5V Æ Boosted voltage will be 8.75V Over-current protection Over-voltage protection □ Control function ： Pre-gain amplifier −6dB ∼ +15dB, 3dB step Built-in Second order lowpass filter at Input. Cutoff Frequency (4kHz,8kHz,16kHz) Power-on/off control Over-temperature protection □ Operational voltage * Adjustable by Pin (PG0, PG1 and PG2) control * Adjustable by Pin (PG0, PG1 and PG2) control ： VBAT=2.7V ∼ 4.5V、DVDDI=1.65V ∼ 4.5V ： −30°C ∼ 85°C □ Operational temperature □ Package ： 31pin WL-CSP (3....