500 mA PWM Step-Down DC-DC with
Synchronous Rectifier
ADP3051
FEATURES GENERAL DESCRIPTION Current mode control for simple loop compensation
Input voltage range: 2.7 V to 5.5 V
Output voltage range: 0.8 V to 5.5 V
Tri-Mode™ operation for high efficiency
550 kHz PWM operating frequency
High accuracy over line, load, and temperature
Micropower shutdown mode
Space-saving MSOP-8 package The ADP3051 is a low noise, current mode, pulse width modulator (PWM) step-down converter capable of supplying over
500 mA to output voltages as low as 0.8 V. This device integrates
a low resistance power switch and synchronous rectifier, providing excellent efficiency over the entire output voltage range and
eliminating the need for a large and costly external Schottky
rectifier. Its 550 kHz switching frequency permits the use of
small external components. APPLICATIONS Current mode control and external compensation allow the
regulator to be easily optimized for a wide range of operating
conditions. The ADP3051 operates at a constant 550 kHz
frequency at medium to heavy loads; it smoothly transitions
into Tri-Mode operation to save power at light loads. A pincontrolled micropower shutdown mode is also included. Li-ion powered handhelds
MP3 players
PDAs and palmtops
Consumer electronics The ADP3051’s 2.7 V to 5.5 V input operating range makes it …