MCP1603

Features:

• Over 90% Typical Efficiency
• Output Current Up To 500 mA
• Low Quiescent Current = 45 A, typical
• Low Shutdown Current = 0.1 A, typical
• Adjustable Output Voltage:
- 0.8V to 4.5V
• Fixed Output Voltage:
-1.2V, 1.5V, 1.8V, 2.5V, and 3.3V
• 2.0 MHz Fixed-Frequency PWM (Heavy Load)
• Automatic PWM to PFM Mode Transition
• 100% Duty Cycle Operation
• Internally Compensated
• Undervoltage Lockout (UVLO)
• Overtemperature Protection
• Space Saving Packages:
- 5-Lead TSOT
- 8-Lead 2X3 DFN




Application

• Cellular Telephones
• Portable Computers
• Organizers / PDAs
• USB Powered Devices
• Digital Cameras
• Portable Equipment
• +5V or +3.3V Distributed Systems




Pinout






Specifications

Parameter NameValueDevice DescriptionStep-down Regulator/Controller CombinationSW Reg Output0.8 to 4.5VTypical Active Supply (A)45Switching Frequency (kHz)2000Output Current (mA)500Output Voltage (V)0.8 to 4.5Input Voltage Range (V)2.7 to 5.5

Parameter Name	Value
Device Description	Step-down Regulator/Controller Combination
SW Reg Output	0.8 to 4.5V
Typical Active Supply (A)	45
Switching Frequency (kHz)	2000
Output Current (mA)	500
Output Voltage (V)	0.8 to 4.5
Input Voltage Range (V)	2.7 to 5.5

V_IN - GND......................................................................+6.0V
All Other I/O ..............................(GND - 0.3V) to (V_IN + 0.3V)
L_X to GND ............................................. -0.3V to (V_IN + 0.3V)
Output Short Circuit Current.................................Continuous
Power Dissipation (Note 5) .........................Internally Limited
Storage Temperature.................................-65°C to +150°C
Ambient Temp. with Power Applied..............-40°C to +85°C
Operating Junction Temperature................-40°C to +125°C
ESD Protection On All Pins:
HBM.............................................................................4 kV
MM..............................................................................300V

† Notice: Stresses above those listed under "Maximum Ratings" may cause permanent damage to the device. This is
a stress rating only and functional operation of the device at those or any other conditions above those
indicated in the operational sections of this specification is not intended. Exposure to maximum rating conditions
for extended periods may affect device reliability.




Description

The MCP1603 is a high efficient, 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 operates in the 2.0 MHz fixed frequency PWM mode which provides a low noise, low output ripple, small-size solution. When the load is reduced to light levels, the MCP1603 automatically changes operation to a 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 to achieve the highest efficiency over the entire operating current range.

The MCP1603 is available with either an adjustable or fixed output voltage. The available fixed output voltage options are 1.2V, 1.5V, 1.8V, 2.5V, 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.