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MIC2951-3.3YM Datasheet, PDF (1/20 Pages) Micrel Semiconductor – 150mA Low-Dropout Voltage Regulator
MIC2950*/2951
150mA Low-Dropout Voltage Regulator
General Description
Features
The MIC2950 and MIC2951 are “bulletproof” micropower
voltage regulators with very low dropout voltage (typically
40mV at light loads and 250mV at 100mA), and very low
quiescent current. Like their predecessors, the LP2950 and
LP2951, the quiescent current of the MIC2950/MIC2951
increases only slightly in dropout, thus pro-longing battery
life. The MIC2950/MIC2951 are pin for pin compatible with
the LP2950/LP2951, but offer lower dropout, lower
quiescent current, reverse battery, and automotive load
dump protection.
The key additional features and protection offered include
higher output current (150mA), positive transient protection
for up to 60V (load dump), and the ability to survive an
unregulated input voltage transient of –20V below ground
(reverse battery).
The plastic DIP and SOIC versions offer additional system
functions such as programmable output voltage and logic
controlled shutdown. The 3-pin TO-92 MIC2950 is pin-
compatible with the older 5V regulators.
These system functions also include an error flag output
that warns of a low output voltage, which is often due to
failing batteries on the input. This may also be used as a
power-on reset. A logic-compatible shutdown input is also
available which enables the regulator to be switched on and
off. This part may also be pin-strapped for a 5 V output, or
programmed from 1.24 V to 29 V with the use of two
external resistors.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
• High accuracy 3.3, 4.85, or 5V, guaranteed 150mA
output
• Extremely low quiescent current
• Low-dropout voltage
• Extremely tight load and line regulation
• Very low temperature coefficient
• Use as regulator or reference
• Needs only 1.5µF for stability
• Current and thermal limiting
• Unregulated DC input can withstand –20V reverse
battery and +60V positive transients
MIC2951 Version Only
• Error flag warns of output dropout
• Logic-controlled electronic shutdown
• Output programmable from 1.24 to 29V
Applications
• Automotive electronics
• Voltage reference
• Avionics
• Cellular telephones
• Battery powered equipment
• SMPS post-regulator
• High efficiency linear power supplies
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Block Diagram
* MIC2950 Discontinuance September 2007.
MM8 is a registered trademark of Micrel, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
February 2010
M9999-021610