MIC5259_06 Datasheet, PDF (1/11 Pages) Micrel Semiconductor – 300mA High PSRR, Low Noise μCap CMOS LDO

MIC5259
300mA High PSRR, Low Noise µCap CMOS LDO
General Description
The MIC5259 is an efficient CMOS voltage regulator
optimized for low-noise applications. It offers 1.5% initial
accuracy, low dropout voltage (300mV at 300mA) and low
ground current (typically 105µA at light load). The
MIC5259 provides a very-low-noise output, ideal for RF
applications where a clean voltage source is required. The
MIC5259 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 MIC5259 provides a TTL-logic-compatible
enable pin. When disabled, power consumption drops to
nearly zero.
The MIC5259 also works with low-ESR ceramic
capacitors, reducing the amount of board space necessary
for power applications; critical issue 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 MIC5259 is available in the 6-pin
2mm × 2mm MLF^® package and the 5-pin Thin SOT-23
package in a wide range of output voltages.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
Features
• Input voltage range: 2.7V to 6.0V
• PSRR = 70dB @ 1kHz
• Low output noise: 30µV(rms)
• Stability with ceramic output capacitors
• Low-dropout: 300mV @ 300mA
• High-output accuracy:
– 1.5% initial accuracy
– 3.0% over temperature
• Low quiescent current: 105µA
• 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
• Industrial portable electronics
• PC peripherals
Typical Application
V_IN
C_IN = 1.0µF
Ceramic
MIC5259-x.xBD5/YD5
1
5
2
Enable
3
4
Shutdown
EN
EN (pin 3) may be
connected directly
to IN (pin 1).
V_OUT
C_OUT = 1.0µF
Ceramic
C_BYP = 0.01µF
ENABLE
SHUTDOWN
V_IN
EN
C_IN = 1.0µF
MIC5259-x.xBML/YML
1
6
2
5
3
4
C_BYP
(optional)
0.01µF
Ultra-Low Noise Regulator Application
V_OUT
C_OUT = 1.0µF
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
September 2006
1
M9999-091406