MIC2800
Digital Power Management IC
2MHz, 600mA DC/DC w/Dual
300mA/300mA Low VIN LDOs
• Integrated power-on reset (OR function for all outputs)
General Description
–
Adjustable delay time
• LOWQ® mode
The MIC2800 is a high performance power management
IC, giving three output voltages with maximum efficiency.
Integrating a 2MHz DC/DC converter with an LDO post
regulator, the MIC2800 gives two high efficiency outputs
with a second, 300mA LDO for maximum flexibility. The
MIC2800 features a LOWQ® mode, reducing the total
current draw while in this mode to less than 30µA. In
LOWQ® mode, the output noise of the DC to DC converter
is 75µVRMS, significantly lower than other converters which
use a PFM light load mode that can interfere with sensitive
RF circuitry.
–
30µA Total IQ when in LOWQ® mode
• Tiny 16-pin 3mm x 3mm MLF® package
DC to DC Converter
• Output current to 600mA in PWM mode
• LOWQ® Mode: NO NOISE Light load mode
–
75µVRMS output noise in LOWQ® mode
• 2MHz PWM operation in normal mode
• >90% efficiency
LDOs
• LDO1 input voltage directly connected to DC/DC
converter output voltage for maximum efficiency
The DC to DC converter uses small values of L and C to
reduce board space but still retains efficiencies over 90%
at load currents up to 600mA.
–
–
–
Ideal for 1.8V to 1.5V conversion
300mA output current from 1.8V input
Output voltage down to 0.8V
The MIC2800 is 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 x 3mm MLF® leadless package.
• LDO2 – 300mA output current capable
• Thermal Shutdown Protection
• Current Limit Protection
Applications
• Mobile phones
• PDAs
• GPS receivers
• Digital still cameras
• Portable media players
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Features
• 2.7V to 5.5V input voltage range
• 2MHz DC/DC converter and two stand-alone LDOs
–
LDO1: Low input voltage is powered directly from
DC/DC converter for highest efficiency
Typical Application
DC/DC 1.8V
Efficiency
OUT
100
95
90
85
80
75
70
65
60
55
50
MIC2800-xxxYML
3.6V
4.2V
3V
VIN
VIN
VIN
LDO
SW
FB
VOUT
2.7V to 5.5V
Memory/DSP
Baseband
4.7µF/
6.3V
2.2µH
2.2µF
ceramic
EN1
LOWQ
EN2
CBYP
CBIAS
LDO1
LDO2
POR
CSET
L = 2.2µH
= 2.2µF
COUT2
2.2µF
ceramic
COUT1
2.2µF
ceramic
CBYP
0.01µF
C
OUT
/LowQ = V
PGND
SGND
IN
CBIAS
0.1µF
CSET
0.01µF
0
100 200 300 400 500 600
OUTPUT CURRENT (mA)
GND
GND
LOWQ is a registered trademark of Micrel, Inc.
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
M9999-090507-C
September 2007