AK7841 Datasheet | Asahi Kasei Microdevices

DESCRIPTION The AK7841 is a Monaural Class-D amplifier for driving Piezo-Electric Speakers. Its built-in power boost DCDC converter generates adequate high voltage for driving Piezo Speaker from a Li-Ion battery. Output filter-less solution eliminates post LC-filters, which are normally required at Class-D outputs, and contributes to total space savings. Class-D operation ensures higher power efficiency. The AK7841 is the most appropriate for Cellular Phones with a piezo speaker. FEATURES - Class-D Amplifier : - Piezo-Electric Speaker Driver - Analog Monaural signal input for both single and Differential-ended - Monaural BTL output - Output voltage = 12Vpp @VDD1=8.75V - Filter-less solution - Pop noise free architecture during power up or down. - Output short protection - Boost DCDC Converter ： - Input voltage = 2.7V ∼ 4.5V Æ Output voltage = 8.75V - Over-current protection - Over-voltage protection - Control function ： - Pre-gain amplifier - 3d B ∼ +18d B, 3d B step. - Power-own control - Over-temperature protection Controlled by pin setting. - Operational voltage ：VBAT=2.7V ∼ 4.5V、DVDDI=1.65V ∼ 4.5V - Operational temperature： - 30°C ∼ 85°C - Package： 24pin WL-CSP (2.5mm × 2.5mm, 0.5mm pitch) Rev.08 -1- 2008/3 ASAHI KASEI [AK7841] .. BLOCK DIAGRAM DVDDI PDN VBAT PD C ont Pow er Booster VCO IL VFB ERRO VSS2 PG 0 PG 1 PG 2 Gain C ontrol VDD1 INN INP Pre AM P -3d B ∼ +18d B 3d B step C lass-D AM P VCN VCP VSS1 SDSEL +16d...