0.65V Start-Up Synchronous Boost Regulator with True Output Disconnect or Input/Output Bypass Option
Description:
The MCP1640/B/C/D is a compact, high-efficiency, fixed frequency, synchronous step-up DC-DC converter. It provides an easy-to-use power supply solution for applications powered by either single-cell, two-cell, or three-cell alkaline, NiCd, NiMH, and single cell Li-Ion or Li-Polymer batteries. Low-voltage technology allows the regulator to start-up without high inrush current or output voltage overshoot from a low 0.65V input. High efficiency is accomplished by integrating the low resistance N-Channel Boost switch and synchronous P-Channel switch. All compensation and protection circuitry is integrated to minimize the number of external components. For standby applications, the MCP1640 consumes only 19 µA while operating at no load, and provides a true disconnect from input to output while in Shutdown (EN = GND). Additional device options are available by operating in PWM-Only mode and connecting input to output while the device is in Shutdown. The “true” load disconnect mode provides input-to-output isolation while the device is disabled by removing the normal boost regulator diode path from input-tooutput. The Input-to Output Bypass mode option connects the input to the output using the integrated low resistance P-Channel MOSFET, which provides a low bias voltage for circuits operating in Deep Sleep mode. Both options consume less than 1 µA of input current.
Features:
• Up to 96% Typical Efficiency
• 800 mA Typical Peak Input Current Limit:
- IOUT > 100 mA @ 1.2V VIN, 3.3V VOUT
- IOUT > 350 mA @ 2.4V VIN, 3.3V VOUT
- IOUT > 350 mA @ 3.3V VIN, 5.0V VOUT
• Low Start-Up Voltage: 0.65V, typical 3.3V VOUT @ 1 mA
• Low Operating Input Voltage: 0.35V, typical 3.3VOUT @ 1 mA
• Adjustable Output Voltage Range: 2.0V to 5.5V
• Maximum Input Voltage < VOUT < 5.5V
• Automatic PFM/PWM Operation (MCP1640/C):
- PFM Operation Disabled (MCP1640B/D)
- PWM Operation: 500 kHz
• Low Device Quiescent Current: 19 µA, typical PFM Mode (not switching)
• Internal Synchronous Rectifier
• Internal Compensation
• Inrush Current Limiting and Internal Soft Start
• Selectable, Logic Controlled Shutdown States:
- True Load Disconnect Option (MCP1640/B)
- Input to Output Bypass Option (MCP1640C/D)
• Shutdown Current (All States): < 1 µA
• Low Noise, Anti-Ringing Control
• Overtemperature Protection
Applications:
• One, Two and Three Cell Alkaline and NiMH/NiCd Portable Products
• Single-Cell Li-Ion to 5V Converters
• Li Coin Cell Powered Devices
• Personal Medical Products
• Wireless Sensors
• Handheld Instruments
• GPS Receivers
• Bluetooth Headsets
• +3.3V to +5.0V Distributed Power Supply
