LM2770_15 Datasheet, PDF (1/20 Pages) Texas Instruments – High Efficiency Switched Capacitor Step-Down DC/DC Regulator with Sleep Mode

LM2770
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SNVS318E – NOVEMBER 2004 – REVISED MAY 2013
LM2770 High Efficiency Switched Capacitor Step-Down DC/DC Regulator with Sleep Mode
Check for Samples: LM2770
FEATURES
1
•2 High Efficiency Multi-Gain Architecture: Peak
Power Efficiency >85%
• Output Voltage Pairs: 1.2V/1.5V and
1.2V/1.575V
• Dynamic Output Voltage Selection
• ±3% Output Voltage Accuracy
• Output Currents up to 250mA
• 2.7V to 5.5V Input Range
• Low-Supply-Current Sleep Mode
• 55µA Quiescent Supply Current in Full-Power
Mode
• Soft-Start
• Short-Circuit Protection in Full-Power Mode
• Current-Limit Protection in Sleep Mode
• WSON-10 Package (3mm × 3mm × 0.8mm)
APPLICATIONS
• DSP Power Supplies
• Baseband Power Supplies
• Mobile Phones and Pagers
• Portable Electronic Equipment
DESCRIPTION
The LM2770 is a switched capacitor step-down
regulator that is ideal for powering low-voltage
applications in portable systems. The LM2770 can
supply load currents up to 250mA and operates over
an input voltage range of 2.7V to 5.5V. This makes
the LM2770 a great choice for systems powered by
1-cell Li-Ion batteries and chargers. The output
voltage of the LM2770 can be dynamically switched
between two output levels with a logic input pin.
Output voltage pairs currently available include
1.2V/1.5V and 1.2V/1.575V. Other pairs of voltage
options can be developed upon request.
Typical Application Circuit
V_IN = 2.7V to
5.5V
9
C_IN
10 PF
LM2770
V_IN
V_OUT
V_OUT :1.2V/1.5V
or 1.2V/1.575V
Dynamic scaling w/ V_SEL
I_OUT up to 250 mA
6
C_OUT
10 PF
C1
1 PF
C2
1 PF
8 ^C1+
7 _C1-
C2+
3
5
C2-
V_{SEL 1}
EN
2
SLEEP
10
GND
4
H: V_OUT-H
L: V_OUT-L
H: ON
L: Shutdown
H: Sleep
L: Full-power
100%
90%
80%
70%
60%
50%
40%
30%
20%
V_OUT = 1.5V
10%
I_OUT = 100 mA
0%
3.0 3.5 4.0 4.5
V_IN (V)
LM2770
LDO
5.0 5.5
Capacitors: 1 PF - TDK C1005X5R0J105K
10 PF - TDK C2012X5R0J106M
or equivalent
Figure 1.
Figure 2. LM2770 Efficiency vs.
Low-Dropout Linear Regulator (LDO) Efficiency
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.
2
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2004–2013, Texas Instruments Incorporated