MCP1252_13 Datasheet, PDF (1/20 Pages) Microchip Technology – Low Noise, Positive-Regulated Charge Pump

MCP1252/3
Low Noise, Positive-Regulated Charge Pump
Features
• Inductorless, Buck/Boost, DC/DC Converter
• Low Power: 80 µA (Typical)
• High Output Voltage Accuracy:
- ±2.5% (V_OUT Fixed)
• 120 mA Output Current
• Wide Operating Temperature Range:
- -40°C to +85°C
• Thermal Shutdown and Short-Circuit Protection
• Uses Small Ceramic Capacitors
• Switching Frequency:
- MCP1252: 650 kHz
- MCP1253: 1 MHz
• Low Power Shutdown Mode: 0.1 µA (Typical)
• Shutdown Input Compatible with 1.8V Logic
• V_IN Range: 2.0V to 5.5V
• Selectable Output Voltage (3.3V or 5.0V) or
Adjustable Output Voltage
• Space-saving, 8-Lead MSOP
• Soft-Start Circuitry to Minimize In-Rush Current
Applications
• White LED Backlighting
• Color Display Bias
• Local 3V-to-5V Conversions
• Flash Memory Supply Voltage
• SIM Interface Supply for GSM Phones
• Smart Card Readers
• PCMCIA Local 5V Supplies
Description
The MCP1252/3 are inductorless, positive-regulated
charge pump DC/DC converters. The devices generate
a regulated fixed (3.3V or 5.0V) or adjustable output
voltage. They are specifically designed for applications
requiring low noise and high efficiency and are able to
deliver up to 120 mA output current. The devices allow
the input voltage to be lower or higher than the output
voltage, by automatically switching between buck/
boost operation.
The MCP1252 has a switching frequency of 650 kHz,
avoiding interference with sensitive IF bands. The
MCP1253 has a switching frequency of 1 MHz and
allows the use of smaller capacitors than the
MCP1252, thus saving board space and cost.
Both devices feature a power-good output that can be
used to detect out-of-regulation conditions. Extremely
low supply current and low external parts count (three
capacitors) make these devices ideal for small, battery-
powered applications. A shutdown mode is also pro-
vided for further power reduction. The MCP1252 and
MCP1253 feature thermal and short-circuit protection
and are offered in space-saving, 8-lead, MSOP
packages.
Package Types
MSOP (FIXED)
PGOOD
V_OUT
V_IN
GND
1
8
2 MCP1252 7
3 ^MCP1253 6
4
5
SELECT
SHDN
C+
C-
MSOP (ADJUSTABLE)
PGOOD
V_OUT
V_IN
GND
1
8
2 _MCP1252 7
3 MCP1253 6
4
5
FB
SHDN
C+
C-
 2002-2013 Microchip Technology Inc.
DS21752B-page 1