MCP16321/2
24V Input, 1A/2A Output, High Efficiency Synchronous Buck Regulator
with Power Good Indication
Features Description
Up to 95% Typical Efficiency The MCP16321/2 is a highly integrated, high-efficiency,
fixed frequency, synchronous step-down DC-DC
Input Voltage Range: 6.0V to 24V
converter in a 16-pin QFN package that operates from
1A Output Current (MCP16321)
input voltages up to 24V. Integrated features include a
2A Output Current (MCP16322)
high-side and low-side N-Channel switch, fixed
Fixed Output Voltages: 0.9V, 1.5V, 1.8V, 2.5V,
frequency Peak Current Mode Control, internal
3.3V, 5V with 2% Output Voltage Accuracy
overvoltage
compensation, peak current limit, V
OUT
Adjustable Version Output Voltage Range:
protection and overtemperature protection. Minimal
0.9V to 5V with 1.5% Reference Voltage Accuracy
external components are necessary to develop a
complete synchronous step-down DC-DC converter
Integrated N-Channel High-Side Switch: 180 m
power supply.
Integrated N-Channel Low-Side Switch: 120 m
1 MHz Fixed Frequency High converter efficiency is achieved by integrating a
high-speed, current limited, low resistance, high-side
Low Device Shutdown Current
N-Channel MOSFET, as well as a high-speed, low
Peak Current Mode Control
resistance, low-side N-Channel MOSFET and
Internal Compensation
associated drive circuitry. High switching frequency
Stable with Ceramic Capacitors
minimizes the size of the inductor and output capacitor,
Internal Soft-Start resulting in a small solution size.
Cycle-by-Cycle Peak Current Limit
The MCP16321/2 device can supply 1A/2A of
Undervoltage Lockout (UVLO): 5.75V continuous current while regulating the output voltage
from 0.9V to 5V. A high-performance peak current
Overtemperature Protection
mode architecture keeps the output voltage tightly
V Overvoltage Protection
OUT
regulated, even during input voltage steps and output
V Voltage Supervisor Reported at the PG Pin
OUT
current transient conditions that are common in power
Available Package: QFN-16 (3x3 mm)
supplies.
The regulator can be turned on and off with a logic level
Applications
signal applied to the EN input. The EN input is internally
pulled up to a 4.2V reference and is rated for a
PIC /dsPIC Microcontroller Bias Supply
maximum of 6V. With EN low, typically 5 A of current
12V Industrial Input DC-DC Conversion
is consumed from the input, making the part ideal for
Set-Top Boxes
power shedding and load distribution applications. The
DSL Cable Modems
PG output is an open drain output pin used to interface
Automotive
with other components of the system, and can be
pulled up to a maximum of 6V.
Wall Cube Regulation
SLA Battery Powered Devices
The output voltage can either be fixed at output
AC-DC Digital Control Power Source voltages of 0.9V, 1.5V, 1.8V, 2.5V, 3.3V, 5V or
adjustable using an external resistor divider. The
Power Meters
MCP16321/2 is offered in a 3x3 QFN-16 surface mount
Consumer
package.
Medical and Health Care
Distributed Power Supplies
2011 Microchip Technology Inc. DS22285A-page 1MCP16321/2
Package Type
MCP16321/2
3x3 QFN*
16 15 14 13
SW SW
1 12
V 11 V
2
IN EP IN
17
BOOST
V 3 10
IN
S EN
4 9
GND
567 8
* Includes Exposed Thermal Pad (EP); see Table 3-1.
Typical Applications
Typical Application with Adjustable Output Voltage
C
BOOST
22 nF
L1
BOOST
V
OUT
4.7 H
4.2V @ 1A/2A
V
IN
SW
6.0V to 24V
V
IN
36.5 k
C
OUT
V
FB
2x22 F
V
OUT
10 k
10 k
C
IN
EN
PG
2x10 F
S P
GND GND
Typical Application with Fixed Output Voltage
C
BOOST
22 nF
L1
V
OUT
BOOST
4.7 H
3.3V @ 1A/2A
V
IN SW
6.0V to 24V
V
IN
C
OUT
2x22 F
V
FB
V
OUT
C
IN
2x10 F
10 k
PG
EN
S P
GND GND
DS22285A-page 2 2011 Microchip Technology Inc.
FB
SW
NC
P
GND
NC P
GND
SW
PG
MCP16321/2
MCP16321/2