MIC2950 Datasheet, PDF (1/14 Pages) Micrel Semiconductor – 150mA Low-Dropout Voltage Regulator

MIC2950/2951
Micrel
MIC2950/2951
150mA Low-Dropout Voltage Regulator
General Description
The MIC2950 and MIC2951 are “bulletproof” micropower ^Features
voltage regulators with very low dropout voltage (typically • High accuracy 3.3, 4.85, or 5V, guaranteed 150mA output
40mV at light loads and 250mV at 100mA), and very low • Extremely low quiescent current
quiescent current. Like their predecessors, the LP2950 and • Low-dropout voltage
LP2951, the quiescent current of the MIC2950/MIC2951 • Extremely tight load and line regulation
increases only slightly in dropout, thus prolonging battery life. • Very low temperature coefficient
The MIC2950/MIC2951 are pin for pin compatible with the • Use as regulator or reference
LP2950/LP2951, but offer lower dropout, lower quiescent • Needs only 1.5µF for stability
current, reverse battery, and automotive load dump protection. • Current and thermal limiting
The key additional features and protection offered include ^{• Unregulated DC input can withstand –20V reverse battery}
higher output current (150mA), positive transient protection
and +60V positive transients
for up to 60V (load dump), and the ability to survive an • Error flag warns of output dropout (MIC2951)
unregulated input voltage transient of –20V below ground • Logic-controlled electronic shutdown (MIC2951)
(reverse battery).
• Output programmable from 1.24V to 29V (MIC2951)
3
The plastic DIP and SOIC versions offer additional system Applications
functions such as programmable output voltage and logic _{• Automotive Electronics}
controlled shutdown. The 3-pin TO-92 MIC2950 is pin- _{• Battery Powered Equipment}
compatible with the older 5V regulators.
• Cellular Telephones
These system functions also include an error flag output that ^{• SMPS Post-Regulator}
warns of a low output voltage, which is often due to failing ^{• Voltage Reference}
batteries on the input. This may also be used as a power-on ^{• Avionics}
reset. A logic-compatible shutdown input is also available ^{• High Efficiency Linear Power Supplies}
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.
Block Diagram
Unregulated
DC Supply ^FB
SHDN
TTL/CMOS
Control Logic
Input
60mV
1.23V
REF.
MIC2951-0x
IN
Error
Amp.
182k
60k
Error Detection
Comparator
OUT
SNS
TAP
ERR
GND
5V/150mA
Output
330k
TTL/CMOS
Compatible
Error Output
1.5µF
February 1999
3-49