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MCP1603_12 Datasheet, PDF (1/34 Pages) Microchip Technology – 2.0 MHz, 500 mA Synchronous Buck Regulator
MCP1603/B/L
2.0 MHz, 500 mA Synchronous Buck Regulator
Features
• Over 90% Typical Efficiency
• Output Current Up To 500 mA
• Low PFM Quiescent Current = 45 µA, typical
(MCP1603/L)
• Low Shutdown Current = 0.1 µA, typical
• Adjustable Output Voltage:
- 0.8V to 4.5V
• Fixed Output Voltage:
- 1.2V, 1.5V, 1.8V, 2.5V, 3.3V (MCP1603/L)
- 1.8V, 3.3V (MCP1603B)
• 2.0 MHz Fixed-Frequency PWM (Heavy Load)
• Automatic PWM-to-PFM Mode Transition
(MCP1603/L)
• PWM Mode Only Option (MCP1603B)
• 100% Duty Cycle Operation
• Internally Compensated
• Undervoltage Lockout (UVLO)
• Overtemperature Protection
• Space Saving Packages:
- 5-Lead TSOT, Two Pinout Types (MCP1603/L)
- 8-Lead 2 x 3 DFN
Applications
• Cellular Telephones
• Portable Computers
• Organizers / PDAs
• USB Powered Devices
• Digital Cameras
• Portable Equipment
• +5V or +3.3V Distributed Systems
• Headsets
General Description
The MCP1603/B/L is a high-efficiency, fully-integrated
500 mA synchronous buck regulator whose 2.7V to
5.5V input voltage range makes it ideally suited for
applications powered from 1-cell Li-Ion or 2-cell/3-cell
NiMH/NiCd batteries.
At heavy loads, the MCP1603/B/L operates in the
2.0 MHz fixed frequency pulse-width modulation
(PWM) mode, which provides a low noise, low-output
ripple, small-size solution. When the load is reduced to
light levels, the MCP1603/L automatically changes
operation to a Pulse Frequency Modulation (PFM)
mode to minimize quiescent current draw from the
battery. No intervention is necessary for a smooth
transition from one mode to another. These two modes
of operation allow the MCP1603/L to achieve the
highest efficiency over the entire operating current
range.
The MCP1603B device disables the PFM mode
switching, and operates only in normal PWM mode
over the entire load range (without skipping).
MCP1603B is for applications that cannot tolerate the
low-frequency output ripple associated with PFM
switching.
The MCP1603/B/L family is available with either an
adjustable or fixed-output voltage. The available fixed
output voltage options for MCP1603/L are 1.2V, 1.5V,
1.8V, 2.5V and 3.3V, and for MCP1603B are 1.8 and
3.3V. When a fixed option is used, only three additional
small external components are needed to form a
complete solution. Couple this with the low profile,
small-foot print packages and the entire system
solution is achieved with minimal size.
Additional protection features include: UVLO,
overtemperature and overcurrent protection.
 2007-2012 Microchip Technology Inc.
DS22042B-page 1