General Description
The MIC33153 is a high-efficiency 4 MHz 1.2A
synchronous buck regulator with an internal inductor,
HyperLight Load® mode, Power Good (PG) output
indicator, and programmable soft-start. HyperLight
Load® provides very high efficiency at light loads and
ultra-fast transient response which makes the
MIC33153 perfectly suited for supplying processor
core voltages.
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 MIC33153 is designed so that only two external
capacitors as small as 2.2 μF are needed for stability.
This gives the MIC33153 the ease of use of an LDO
with the efficiency of a HyperLight Load® DC converter.
The MIC33153 achieves efficiency in HyperLight
Load® mode as high as 85% at 1 mA, with a very low
quiescent current of 22 μA. At higher loads, the
MIC33153 provides a constant switching frequency up
to 4 MHz.
The MIC33153 is available in 14-lead 3.0 mm x 3.5 mm
TDFN package with an operating junction temperature
range from –40°C to +125°C.

Features
• Internal Inductor
• Simplifies Design to Two External Capacitors
• Input Voltage: 2.7V to 5.5V
• Output Voltage: Fixed or Adjustable (0.62V to 3.6V)
• Up to 1.2A Output Current
• Up to 93% Peak Efficiency
• 85% Typical Efficiency at 1 mA
• Power Good (PG) Output
• Programmable Soft-Start
• 22 μA Typical Quiescent Current
• 4 MHz PWM Operation in Continuous Mode
• Ultra-Fast Transient Response
• Low Ripple Output Voltage
- 35 mVPP Ripple in HyperLight Load® Mode
- 7 mV Output Voltage Ripple in Full PWM Mode
• 0.01 μA Shutdown Current
• Thermal Shutdown and Current Limit Protection
• 14-lead 3.0 x 3.5 x 1.1 mm TDFN Package
• –40°C to +125°C Junction Temperature Range

Applications
• Solid State Drives (SSD)
• Mobile Handsets
• Portable Media/MP3 Players
• Portable Navigation Devices (GPS)
• WiFi/WiMax/WiBro Modules
• Wireless LAN Cards
• Portable Applications