• DCw/DwCw.SDtaetapS-uhepeCt4oUn.cvoemrter (BOOST) 3.3V to 5.2V, 1A, up to 90% Efficiency. Can be Used
as BUCK/BOOST in SEPIC Configuration
• DC/DC Step-down (BUCK) Synchronous Converter 0.9V to 3.4V, 500mA, up to 90%
Efficiency, Pulse Skipping Capabilities for High Efficiency at Light Load Currents
• Two Low-Drop-Out Regulators 1.3V, 1.5V to 1.8V, 2.5V to 2.8V (100 mV Step), 3.3V,
200 mA Maximum Load
• Ultra-low Power Real-time Clock (RTC) and Backup Battery Management
– 2.6V RTC LDO for Backup Battery Charging
– 32 kHz Crystal RTC Oscillator (1 µA)
– RTC Circuit for Time and Date Information
• Activation of the Power Management Modules via Dedicated Enable Pin
• Automatic Start-up Sequences, POK Signal Indicating When Start-up is Completed
• Activation and Control of the Power Management Modules in Dynamic Mode (via SPI or
TWI) or in Static Mode (On/Off of the Four Power Supplies)
• ITB Signal Indicating Short-circuits in DC/DC Converters
• Very Low Quiescent Current
• Minimum External Components Count
• Supply: from 2.8V to 5.25V (typ: Li-Ion Battery 3V to 4.2V)
• Available in a 32-pin 5x5 QFN Package
• Applications Include:
– WLAN Portable Devices
– Multimedia Devices
– Portable Music Players
The AT73C224-x is a family of ultra low cost Power Management Unit, available in a
small outline QFN 5x5mm package.
The AT73C224-x family is optimized for portable applications, typically powered by a
Li-Ion battery. The AT73C224-x device is also suitable to operate from a standard
3.3V to 5.25V voltage rail. It includes four power supplies and a very low power Real-
time Clock (RTC). In normal mode (main battery present), the backup battery is
recharged through a 2.6V RTC LDO.
The AT73C224-x series offer different automatic start-up sequences (with varying
orders of power-on and specific default output values) and different soft management
modes: dynamic (via SPI or TWI) with register access or static, with access to power
on/off of the four power supplies.
Each AT73C224-x device is equipped with a very low power bandgap reference, low
power 32 kHz and 1 MHz oscillators and an internal LDO used to generate the internal
supply (VINT) equal to 2.8V. Auxiliary cells, such as a power-on reset (POR) and a
voltage monitor are used to control the system power-on (battery plugged in) and
power-off (battery unplugged).
The four power supplies are named: BOOST1, BUCK2, LDO3 and LDO4.
Table 1-1 lists the different devices available in the AT73C224-x series.