Features: `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
`55A Quiescent Supply Current in Full-Power Mode
`Soft-Start
`Short-Circuit Protection in Full-Power Mode
`Current-Limit Protection in Sleep Mode
`LLP-10 Package (3mm x 3mm x 0.8mm)Application·DSP Power Supplies
·Baseband Power Supplies
·Mobile Phones and Pagers
·Portable Electronic EquipmentPinout
SpecificationsIf Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
VIN Pin Voltage ........................................-0.3V to 6.0V
EN, SLEEP, and VSEL Pin Voltages. -0.3V to (VIN+0.3V)
.............w/ 6.0V max
Continuous Power Dissipation............Internally Limited
(Note 3)
VOUT Short to GND Duration...............................Infinite
(Note 4)
Junction Temperature (TJ-MAX) .............................150
Storage Temperature Range................ -65 to +150
Maximum Lead Temperature.................................265
(Note 5)
ESD Rating (Note 6)
Human Body Model:.............................................2.0kV
Machine Model......................................................200V
DescriptionThe 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.
LM2770 efficiency is superior to both fixed-gain switched capacitor buck regulators and low-dropout linear regulators (LDO's). Multiple fractional gains maximize power efficiency over the entire input voltage and output current ranges. The LM2770 can also be switched into a low-power sleep mode when load currents are light (<= 20mA). In sleep mode, the charge pump is off, and the output is driven with a low-noise, low-power linear regulator.
Soft-start, short-circuit protection, current-limit protection, and thermal-shutdown protection are also included. The LM2770 is available in National's small 10-pin Leadless Leadframe Package (LLP-10).
Reliability Metrics
| Part Number |
Process |
EFR Reject |
EFR Sample Size |
PPM |
LTA Rejects |
LTA Device Hours |
FITS |
MTTF (Hours) |
| LM2770SD-1215 |
CMOS7 |
0 |
16561 |
0 |
0 |
954000 |
4 |
270700104 |
| LM2770SD-12157 |
CMOS7 |
0 |
16561 |
0 |
0 |
954000 |
4 |
270700104 |
| LM2770SDX-1215 |
CMOS7 |
0 |
16561 |
0 |
0 |
954000 |
4 |
270700104 |
| LM2770SDX-12157 |
CMOS7 |
0 |
16561 |
0 |
0 |
954000 |
4 |
270700104 |
Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.For more information on Reliability Metrics, please click here.
More Application Notes
| Title |
Size in Kbytes |
Date |
|
| AN-1769: Application Note 1769 LM2773 Evaluation Board |
419 Kbytes |
2-Jun-08 |
Download |
| AN-1547: Application Note 1547 LM2771 Evaluation Board |
670 Kbytes |
3-Nov-06 |
Download |
AN-1547 (Chinese): Application Note 1547 LM2771 Evaluation Board
|
252 Kbytes |
|
640){this.height=this.height*640/this.width;this.width=640;}' border="0" alt=" Connection Diagram"> |
| AN-1714: Application Note 1714 LM2772 Evaluation Board |
391 Kbytes |
18-Sep-07 |
Download |
If you have trouble printing or viewing PDF file(s), see Printing Problems.
|
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.
LM2770 efficiency is superior to both fixed-gain switched capacitor buck regulators and low-dropout linear regulators (LDO's). Multiple fractional gains maximize power efficiency over the entire input voltage and output current ranges. The LM2770 can also be switched into a low-power sleep mode when load currents are light ( 20mA). In sleep mode, the charge pump is off, and the output is driven with a low-noise, low-power linear regulator.
Soft-start, short-circuit protection, current-limit protection, and thermal-shutdown protection are also included. The LM2770 is available in National's small 10-pin Leadless Leadframe Package (LLP-10).
LM2770 Data Sheet
