Alpha & Omega Semi Introduces Synchronous Buck Regulator Family
Alpha & Omega Semiconductor, Inc. (AOS) introduced a family of synchronous EZBuck™ dc-dc step-down converters. The 2A (AOZ1020), 3A (AOZ1021 and AOZ1022), and 4A (AOZ1024) products are designed for conversions from 4.5 to 16V input voltages.
The new products are suitable for networking, computing, consumer and industrial markets for powering low voltage rails in cable and DSL modems, set-top boxes, portable navigation devices, portable DVD players, DVD recorders, LCD TVs, industrial control systems, servers, graphics cards, ultramobile PCs as well as high-end desktops.
The AOZ1020, AOZ1021, AOZ1022 and AOZ1024 are said to provide efficient step-down converter solutions for low duty cycle applications. The parts operate at 500kHz switching frequency reducing the size of the output filter components. The AOZ1020 and AOZ1021 are rated at 2 and 3A, respectively, and are available in an SO-8 package. The AOZ1022 and AOZ1024 are rated at 3 and 4A, respectively, and are available in the DFN5x4-8L package. The DFN package has improved thermal performance allowing operation in higher ambient temperature conditions.
The new devices are current-mode PWM step-down regulators with an integrated high side PMOS and low side NMOS switch. The high-side PMOS not only simplifies gate driver circuitry, but also allows for 100% duty cycle operation allowing a wide 0.8 to 15V range of output voltages. AOS’ proprietary Trench MOSFET technology enables RDS(ON) as low as 100mΩ on the high side and 20mΩ on the low side, thus reducing power losses.
The devices feature a TTL compatible enable input and also have a fixed internal soft start time of 4ms. The devices are protected with features such as input under-voltage lockout, cycle-by-cycle current limit and thermal shutdown. The AOZ1020 and AOZ1022 also offer an open drain power good indicator (PGOOD). The PGOOD function is required by many processor core voltages and also can be used to simplify sequencing requirements and enable more reliable system operation.
The AOZ102x family is available immediately in production quantities, and priced as follows (1K price USD): AOZ1020AI – 0.82; AOZ1021AI – 0.85; AOZ1022DI – 0.92; and AOZ1024DI – 0.95.
