Microchip Technology MCP1256/7/8/9EV Data Sheet

 2006-2013 Microchip Technology Inc.

DS21989B-page 1

• Inductorless 1.5x, 2x Boost DC/DC Converter

• Output Voltage: 3.3V

• High Output Voltage Accuracy: 

- ±3.0% (V

OUT

 Fixed)

• Output Current Up To 100 mA

• 20 mV

PP

 Output Voltage Ripple

• Thermal Shutdown and Short Circuit Protection

• Uses Small Ceramic Capacitors

• Switching Frequency: 650 kHz

• Low-Power SLEEP Mode: MCP1256/7

• BYPASS Mode: MCP1258/9

• Low-Power Shutdown Mode: 0.1 µA (Typical)

• Shutdown Input Compatible with 1.8V Logic

• V

IN

 Range: 1.8V to 3.6V

• Soft-Start Circuitry to Minimize Inrush Current

• Temperature Range: -40°C to +125°C

• Packaging:

- 10-Pin, 3 mm x 3 mm DFN

- 10-Pin,  MSOP

• Pagers

• Portable Measurement Instruments

• Home Automation Products

• PIC

®

 MCU Bias

The MCP1256, MCP1257, MCP1258 and MCP1259
are inductorless, positive regulated charge pump
DC/DC converters. The devices generate a regulated
3.3V output voltage from a 1.8V to 3.6V input. The
devices are specifically designed for applications
operating from 2-cell alkaline, Ni-Cd, or Ni-MH
batteries or by one primary lithium MnO2 (or similar)
coin cell battery. 

The MCP1256, MCP1257, MCP1258 and MCP1259
provide high efficiency by automatically switching
between 1.5x and 2x boost operation. In addition, at
light output loads, the MCP1256 and MCP1257 can be
placed in a SLEEP mode, lowering the quiescent
current while maintaining the regulated output voltage.
Alternatively, the MCP1258 and MCP1259 provide a
BYPASS feature connecting the input voltage to the
output. This allows for real-time clocks,
microcontrollers or other system devices to remain
biased with virtually no current being consumed by the
MCP1258 or MPC1259.

In normal operation, the output voltage ripple is below
20 mV

PP

 at load currents up to 100 mA. Normal opera-

tion occurs at a fixed switching frequency of 650 kHz,
avoiding interference with sensitive IF bands.

The MCP1256 and MCP1258 feature a power-good
output that can be used to detect out-of-regulation
conditions. The MCP1257 and MCP1259 feature a low-
battery indication that issues a warning if the input
voltage drops below a preset voltage threshold.
Extremely low supply current and few external parts (4
capacitors) make these devices ideal for small, battery-
powered applications. A Shutdown mode is also
provided for further power reduction. 

The devices incorporate thermal and short-circuit pro-
tection. Two package offerings are provided: 10-pin
MSOP and 10-lead 3 mm x 3 mm DFN. The devices
are completely characterized over the junction temper-
ature range of -40°C to +125°C.

PGOOD

GND

SHDN

1

2

3

4

V

OUT

5

6

7

8

9

10

V

IN

SLEEP

C

IN

10 µF

C

OUT

 

10 µF

C

1

-

C

1

+

C

1

 

1 µF

C

2

-

C

2

+

C

2

 

1 µF

R

1

INPUT 

1.8V to 3.6V

OUTPUT

3.3V

Power-Good  
Indication

ON / OFF

Typical Application with Power-Good Indication