Products

TD8577 5V 2.1A 1.2MHz Synchronous Boost Converter

The TD8577 devices provide a power supply solution for products powered by either a one-cell Li-Ion or Li-polymer, or a two to three-cell alkaline, NiCd or NiMH battery. The converter generates a stable output voltage that is adjusted by an external resistor divider or fixed internally on the chip. It provides high efficient power conversion and is capable of delivering output currents up to 1 A at 5 V at a supply voltage down to 1.8 V. The implemented boost converter is based on a fixed frequency, pulse-width- modulation (PWM) controller using a synchronous rectifier to obtain maximum efficiency. At low load currents the converter enters Power Save mode to maintain a high efficiency over a wide load current range. The Power Save mode can be disabled, forcing the converter to operate at a fixed switching frequency. It can also operate synchronized to an external clock signal that is applied to the SYNC pin. the maximum peak current in the boost switch is limited to a value of 5000 mA.

The converter can be disabled to minimize battery drain. During shutdown, the load is completely disconnected from the battery. A low-EMI mode is implemented to reduce ringing and, in effect, lower

radiated electromagnetic energy when the converter enters the discontinuous conduction mode. The device is packaged in a 16-pin QFN package measuring 4 mm x 4 mm (RSA) or in a 16-pin TSSOP16.or in a DFN3x3-12 packages

Features

92% Efficient Synchronous Boost Converter With 1000-mA Output Current From 1.8-V Input

Device Quiescent Current: 20-μA (Typ)

Input Voltage Range: 1.8-V to 5.5-V

Adjustable Output Voltage Options Up to 5.5-V

Power Save Mode for Improved Efficiency at Low Output Power

Low Battery Comparator

Low EMI-Converter (Integrated Antiringing Switch)

Load Disconnect During Shutdown

Over-Temperature Protection

Available in a Small 4 mm x 4 mm QFN-16 or in a TSSOP-16 or in a DFN3*3-12 package

Applications

Power Bank

Tablet

Portable Equiment

Typical Application Circuit