MIC2168A Datasheet, PDF (1/18 Pages) Micrel Semiconductor – 1MHz PWM Synchronous Buck Control IC

MIC2168A
1MHz PWM Synchronous Buck-Control IC
General Description
The MIC2168A is a high-efficiency, simple to use 1MHz
PWM synchronous buck-control IC housed in a small
MSOP-10 package. The MIC2168A allows compact
DC/DC solutions with a minimal external component
count and cost.
The MIC2168A operates from a 3V to 14.5V input,
without the need of any additional bias voltage. The
output voltage can be precisely regulated down to 0.8V.
The adaptive all N-Channel MOSFET drive scheme
allows efficiencies over 95% across a wide load range.
The MIC2168A senses current across the high-side N-
Channel MOSFET, eliminating the need for an
expensive and lossy current-sense resistor. Current limit
accuracy is maintained by a positive temperature
coefficient that tracks the increasing R_DS(ON) of the
external MOSFET. Further cost and space are saved
by the internal in-rush-current limiting and digital soft-
start.
The MIC2168A is identical to the MIC2168 with the
exception that the MIC2168A increases the overcurrent
blanking time from 80ns (typ.) to 120ns (typ.)
The MIC2168A is available in a 10-pin MSOP package,
with a wide junction operating range of –40°C to
+125°C.
All support documentation can be found on Micrel’s web
site at www.micrel.com.
Features
• 3V to 14.5V input voltage range
• Adjustable output voltage down to 0.8V
• Up to 95% efficiency
• 1MHz PWM operation
• Adjustable current-limit senses high-side N-Channel
MOSFET current
• No external current sense resistor
• Adaptive gate drive increases efficiency
• Ultra-fast response with hysteretic transient recovery
mode
• Overvoltage protection protects the load in fault
conditions
• Dual mode current limit speeds up recovery time
• Hiccup mode short-circuit protection
• Internal soft-start
• Small-size MSOP 10-pin package
Applications
• Point-of-load DC/DC conversion
• Set-top boxes
• Graphic cards
• LCD power supplies
• Telecom power supplies
• Networking power supplies
• Cable modems and routers
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Typical Application
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
January 2010
M9999-011510