MCP1661 Datasheet, PDF (1/34 Pages) Microchip Technology – High-Voltage Integrated Switch PWM Boost Regulator with UVLO

MCP1661
High-Voltage Integrated Switch PWM Boost Regulator with UVLO
Features
• 36V, 800 m Integrated Switch
• Up to 92% Efficiency
• High Output Voltage Range: up to 32V
• 1.3A Peak Input Current Limit:
- I_OUT > 200 mA @ 5.0V V_IN, 12V V_OUT
- I_OUT > 125 mA @ 3.3V V_IN, 12V V_OUT
- I_OUT > 100 mA @ 4.2V V_IN, 24V V_OUT
• Input Voltage Range: 2.4V to 5.5V
• Undervoltage Lockout (UVLO):
- UVLO @ V_IN Rising: 2.3V, typical
- UVLO @ V_IN Falling: 1.85V, typical
• No Load Input Current: 250 µA, typical
• Sleep mode with 200 nA Typical Quiescent
Current
• PWM Operation with Skip mode: 500 kHz
• Feedback Voltage Reference: V_FB = 1.227V
• Cycle-by-Cycle Current Limiting
• Internal Compensation
• Inrush Current Limiting and Internal Soft Start
• Output Overvoltage Protection (OVP) in the event
of:
- Feedback pin shorted to GND
- Disconnected feedback divider
• Overtemperature Protection
• Easily Configurable for SEPIC or Flyback
Topologies
• Available Packages:
- 5-Lead SOT-23
- 8-Lead 2x3 TDFN
Applications
• Two and Three-Cell Alkaline, Lithium Ultimate and
NiMH/NiCd Portable Products
• Single-Cell Li-Ion to 5V, 12V or 24V Converters
• LCD Bias Supply for Portable Applications
• Camera Phone Flash
• Portable Medical Equipment
• Hand-Held Instruments
• Single-Cell Li-Ion to 3.0V or 3.3V SEPIC
Applications (see Figure 6-3)
General Description
The MCP1661 device is a compact, high-efficiency,
fixed-frequency, non-synchronous step-up DC-DC
converter which integrates a 36V, 800 m NMOS
switch. It provides a space-efficient high-voltage
step-up power supply solution for applications powered
by either two-cell or three-cell alkaline, Ultimate Lithium,
NiCd, NiMH, one-cell Li-Ion or Li-Polymer batteries.
The integrated switch is protected by the 1.3A
cycle-by-cycle inductor peak current limit operation.
There is an output overvoltage protection which turns
off switching in case the feedback resistors are
accidentally disconnected or the feedback pin is
short-circuited to GND.
Low-voltage technology allows the regulator to start-up
without high inrush current or output voltage overshoot
from a low-voltage input. The device features a UVLO
which avoids start-up and operation with low inputs or
discharged batteries for two cell-powered applications.
For standby applications (EN = GND), the device stops
switching, enters Sleep mode and consumes 200 nA
(typical) of input current.
MCP1661 is easy to use and allows creating classic
boost, SEPIC or flyback DC-DC converters within a
small Printed Circuit Board (PCB) area. All
compensation and protection circuitry is integrated to
minimize the number of external components. Ceramic
input and output capacitors are used.
Package Types
MCP1661
SOT-23
SW 1
GND 2
V_FB 3
5 V_IN
4 EN
MCP1661
2x3 TDFN*
V_FB 1
8 EN
S_GND 2 _EP 7 P_GND
SW 3
9
6 NC
NC 4
5 V_IN
* Includes Exposed Thermal Pad (EP); see Table 3-1.
 2014-2015 Microchip Technology Inc.
DS20005315B-page 1