MCP1640/B/C/D
0.65V Start-up Synchronous Boost Regulator with True
Output Disconnect or Input/Output Bypass Option
Features
• Up to 96% Typical Efficiency
• 800 mA Typical Peak Input Current Limit:
- I
OUT
> 100 mA @ 1.2V V
IN
, 3.3V V
OUT
- I
OUT
> 350 mA @ 2.4V V
IN
, 3.3V V
OUT
- I
OUT
> 350 mA @ 3.3V V
IN,
5.0V V
OUT
• Low Start-up Voltage: 0.65V, typical 3.3V V
OUT
@ 1 mA
• Low Operating Input Voltage: 0.35V, typical
3.3V
OUT
@ 1 mA
• Adjustable Output Voltage Range: 2.0V to 5.5V
• Maximum Input Voltage
V
OUT
< 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
• 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
• Available Packages:
- SOT23-6
- 2x3 8-Lead DFN
General Description
The MCP1640/B/C/D is a compact, high-efficiency,
fixed frequency, synchronous step-up DC-DC con-
verter. It provides an easy-to-use power supply solution
for applications powered by either one-cell, two-cell, or
three-cell alkaline, NiCd, NiMH, one-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 are integrated to
minimize external components. For standby
applications, the MCP1640 operates and consumes
only 19 µA while operating at no load and provides a
true disconnect from input to output while shut down
(EN = GND). Additional device options are available
that operate in PWM only mode and connect input to
output bypass while shut down.
A “true” load disconnect mode provides input to output
isolation while disabled by removing the normal boost
regulator diode path from input to output. A bypass
mode option connects the input to the output using the
integrated low resistance P-Channel MOSFET, which
provides a low bias keep alive voltage for circuits
operating in Deep Sleep mode. Both options consume
less than 1 µA of input current.
Output voltage is set by a small external resistor
divider. Two package options, SOT23-6 and 2x3
DFN-8, are available.
Package Types
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
MCP1640
6-Lead SOT23
SW 1
GND 2
EN 3
6 V
IN
5 V
OUT
4 V
FB
MCP1640
2x3 DFN*
V
FB
1
S
GND
2
P
GND
3
EN 4
EP
9
8 V
IN
7 V
OUTS
6 V
OUTP
5 SW
* Includes Exposed Thermal Pad (EP); see
2010 Microchip Technology Inc.
DS22234A-page 1
MICROCHIP [ MICROCHIP TECHNOLOGY ]
