MIC33263 Datasheet, PDF (1/19 Pages) Micrel Semiconductor – Buck Regulator with Integrated Inductor

MIC33263/4
4MHz, 2A Buck Regulator with Integrated
Inductor and HyperLight Load^®
General Description
The MIC33263/4 is a highly-efficient synchronous buck
regulator with an integrated inductor which provides the
optimal trade-off between footprint and efficiency. The
MIC33263/4 operates at 4MHz switching frequency and
provides up to 2A output current. In addition, the 100%
duty cycle and HyperLight Load^® (HLL) mode-of-operation
delivers very-high efficiency at light loads and ultra-fast
transient response which makes the MIC33263/4 perfectly
suited for any space-constrained application and great
alternative for low dropout regulators. An additional benefit
of this proprietary architecture is very low output ripple
voltage throughout the entire load range with the use of
small output capacitors.
The MIC33263/4 provides small compact total solution
size of 4.6mm × 7mm with very few tiny external
components.
At higher loads, the MIC33263/4 provides a constant
switching frequency around 4MHz while achieving peak
efficiencies up to 93%. It also includes under-voltage
lockout to ensure proper operation under power-sag
conditions, internal soft-start to reduce inrush current,
foldback current limit, power good (PG) indicator, and
thermal shutdown. The MIC33263/4 is available in a 20-pin
2.5mm × 3.0mm × 1.9mm QFN package with an operating
junction temperature range from –40°C to +85°C.
Datasheets and support documentation are available on
Micrel’s web site at: www.micrel.com.
Features
• Integrated MOSFETs, inductor
• 100% duty cycle
• 4MHz PWM operation in continuous mode
• 2A output current
• Low output voltage ripple
• 85% typical efficiency at 1mA and up to 93% peak
efficiency
• Ultra-fast transient response
• Advanced copper lead frame design provides superior
thermal performance
• Thermal-shutdown and current-limit protection
• Low-radiated emission (EMI) per EN55022, class B
• Adjustable output voltage 0.7V to 5V
• Configurable soft-start with pre-bias start-up capability
• Auto discharge of 180Ω (MIC33264 only)
• Low profile 2.5mm × 3.0mm × 1.9mm QFN packages
• 0.1µA shutdown current
• 33µA quiescent current
Applications
• 5V point-of-load (POL)
• Low voltage distributed power systems
• Space-constrained applications
• Portable devices
• SSD storage systems
• Digital cameras
Typical Application
Efficiency vs.
Output Current
100
90
80
70
VOUT = 2.5V
VOUT = 1.8V
60
VOUT = 3.3V
50
40
30
20
10
10
VIN = 5V
100
1000
OUTPUT CURRENT(mA)
HyperLight Load is a registered trademark of Micrel, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
May 15, 2014
Revision 1.1