MIC5247_06 Datasheet, PDF (1/11 Pages) Micrel Semiconductor – 150mA Low-Voltage μCap Linear Regulator

MIC5247
Micrel, Inc.
MIC5247
150mA Low-Voltage µCap Linear Regulator
General Description
The MIC5247 is an efficient and precise, low-voltage CMOS
voltage regulator optimized for ultra-low noise applications.
The MIC5247 offers better than 1% initial accuracy and
85µA constant ground current over load (typically 85µA).
The MIC5247 provides a very low-noise output, ideal for
RF applications where quiet voltage sources are required.
A noise bypass pin is also available for further reduction of
output noise.
Designed specifically for handheld and battery-powered de-
vices, the MIC5247 provides a logic compatible enable pin.
When disabled, power consumption drops nearly to zero.
The MIC5247 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, a push-
pull output for faster transient response, and an active clamp
to speed up device turnoff. Available in the 6-pin 2mm × 2mm
MLF™ package and the IttyBitty^® SOT-23-5 package, the
MIC5247 also offers a range of fixed output voltages.
All support documentation can be found on Micrel’s web site
at www.micrel.com.
Features
• Ultra-low noise
• Low-voltage outputs
• Load independent, ultra-low ground current: 85µA
• 150mA output current
• Current limiting
• Thermal shutdown
• Tight load and line regulation
• “Zero” off-mode current
• Stability with low-ESR capacitors
• Fast transient response
• Logic-controlled enable input
Applications
• Cellular phones and pagers
• Cellular accessories
• Battery-powered equipment
• Laptop, notebook, and palmtop computers
• PCMCIA V_CC and V_PP regulation/switching
• Consumer/personal electronics
• SMPS post-regulator/DC-to-DC modules
• High-efficiency linear power supplies
Typical Application
V_IN
MIC5247-x.xBM5
1
5
V_OUT
2
Enable
Shutdown
3
EN
EN (pin 3) may be
connected directly
to IN (pin 1).
C_OUT
4
C_BYP
(optional)
ENABLE
SHUTDOWN
V_IN
EN
MIC5247-x.xBML
1
6
2
5
3
4
C_BYP
(optional)
V_OUT
C_OUT
Ultra-Low-Noise Regulator Application
Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
February 2006
1
M9999-022406