MIC5252_04 Datasheet, PDF (1/9 Pages) Micrel Semiconductor – 150mA High PSRR, Low Noise μCap CMOS LDO

MIC5252
Micrel, Inc.
MIC5252
150mA High PSRR, Low Noise µCap CMOS LDO
General Description
The MIC5252 is an efficient, precise CMOS voltage regulator
optimized for ultra-low-noise applications. It offers 1% initial
accuracy, extremely-low dropout voltage (135mV at 150mA)
and low ground current (typically 90µA). The MIC5252
provides a very-low-noise output, ideal for RF applications
where a clean voltage source is required. The MIC5252 has
a high PSRR even at low supply voltages, critical for battery
operated electronics. A noise bypass pin is also available for
further reduction of output noise.
Designed specifically for handheld and battery-powered
devices, the MIC5252 provides a TTL-logic-compatible en-
able pin. When disabled, power consumption drops nearly
to zero.
The MIC5252 also works with low-ESR ceramic capacitors,
reducing the amount of board space necessary for power
applications, critical in handheld wireless devices.
Key features include current limit, thermal shutdown, faster
transient response, and an active clamp to speed up device
turn-off. The MIC5252 is available in the 6-pin 2mm × 2mm
MLF™ package and the IttyBitty® SOT-23-5 package in a
wide range of output voltages.
Features
• Input voltage range: 2.7V to 6.0V
• PSRR = 50dB @ V_O + 0.3V
• Ultra-low output noise: 30µV(rms)
• Stability with ceramic output capacitors
• Ultra-low dropout: 135mV @ 150mA
• High output accuracy:
1.0% initial accuracy
2.0% over temperature
• Low quiescent current: 90µA
• Tight load and line regulation
• TTL-Logic-controlled enable input
• “Zero” off-mode current
• Thermal shutdown and current limit protection
Applications
• Cellular phones and pagers
• Cellular accessories
• Battery-powered equipment
• Laptop, notebook, and palmtop computers
• Consumer/personal electronics
Typical Application
C _IN = 1.0µF ^VIN
Ceramic
Enable
Shutdown
EN
EN (pin 3) may be
connected directly
to IN (pin 1).
MIC5252-x.xBM5
1
5
2
3
4
V _OUT
C _OUT = 1.0µF
Ceramic
ENABLE
SHUTDOWN
C _BYP = 0.01µF
V_IN
MIC5252-x.xBML
V_OUT
EN
1
6
C_BYP
C_OUT
2
5
(optional)
3
4
Ultra-Low-Noise Regulator Application
IttyBitty is a registered trademark of Micrel, Inc.
MicroLeadFrame and MLF are trademarks of Amkor Technology.
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
February 2005
1
M9999-020305