MIC2811_08 Datasheet, PDF (1/17 Pages) Micrel Semiconductor – Digital Power Management IC 2MHz, 600mA DC/DC with Triple 300mA LDOs

MIC2811/2821
Digital Power Management IC
2MHz, 600mA DC/DC with
Triple 300mA LDOs
General Description
Features
The MIC2811/21 are high performance power
management ICs, supporting four output voltage rails with
maximum efficiency. The four rails are generated by a
single 600mA DC/DC converter and three 300mA LDOs.
LDO1 and LDO2 are capable of operating at a low input
voltage down to 1.65V useful for post regulating the output
voltage of the DC-DC converter. The MIC2811 supports
the use of a bypass cap for improved noise performance
on LDO1 & LDO2 while the MIC2821 offers a separate
enable pin for LDO3.
• 2MHz DC/DC converter and 3 LDOs
• Tiny 16-pin 3mm x 3mm MLF^® package
• Thermal Shutdown Protection
• ±2% Output Voltage Accuracy on all outputs
• Current Limit Protection
DC/DC Converter
• 2.7V to 5.5V input voltage range
• Output current to 600mA
Featuring an operating frequency of 2MHz, the DC to DC
converter uses small values of L and C to reduce board
space but still retains operating efficiencies up to 86% at
load currents up to 600mA.
The MIC2811/21 feature a µCap design, operating with
very small ceramic output capacitors and inductors for
stability, reducing required board space and component
cost and it is available in fixed output voltages in the 16-
pin 3mm × 3mm MLF^® leadless package.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
• 2MHz PWM operation
• Up to 86% efficiency (1.2V output)
LDO 1 & 2
• 1.65V to 5.5V input voltage range
• 300mA output current
• Fixed Output voltage as low as 0.8V
• Low 142mV dropout
• 70dB PSRR at 1kHz
LDO 3
• 2.7V to 5.5V input voltage range
Applications
• Mobile phones / PDAs
• 300mA output current
• Fixed Output voltage as low as 1.0V
• Portable media players
• Mobile Television Receivers
____________________________________________________________________________________________________________
Typical Application
1.2VOUT Efficiency
100
90
80
70
60
50
40
30
20
10
00
3V
3.6V
4.2V
L = 2.2µH
C = 2.2µF
100 200 300 400 500 600
OUTPUT CURRENT (mA)
MicroLeadFrame and MLF 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
April 2008
M9999-042208-A