|
|
Número de pieza | LM2788 | |
Descripción | 120mA High Efficiency Step-Down Switched Capacitor Voltage Converter | |
Fabricantes | National Semiconductor | |
Logotipo | ||
Hay una vista previa y un enlace de descarga de LM2788 (archivo pdf) en la parte inferior de esta página. Total 12 Páginas | ||
No Preview Available ! October 2002
www.DataSheet4U.com
LM2788
120mA High Efficiency Step-Down Switched Capacitor
Voltage Converter
General Description
The LM2788 switched capacitor step-down DC/DC con-
verter efficiently produces a 120mA regulated low-voltage
rail from a 2.6V to 5.5V input. Fixed output voltage options of
1.5V, 1.8V, and 2.0V are available. The LM2788 uses mul-
tiple fractional gain configurations to maximize conversion
efficiency over the entire input voltage and output current
ranges. Also contributing to high overall efficiency is the
extremely low supply current of the LM2788: 32µA operating
unloaded and 0.1µA in shutdown.
The optimal external component requirements of the
LM2788 solution minimize size and cost, making the part
ideal for Li-Ion and other battery powered designs. Two 1µF
flying capacitors and two 10µF bypass capacitors are all that
are required, and no inductors are needed.
The LM2788 also features noise-reducing soft-start circuitry,
short-circuit protection and over-temperature protection.
Features
n Output voltage options:
2.0V ± 5%, 1.8V ± 5%, 1.5V ± 6%
n 120mA output current capability
n Multi-Gain and Gain Hopping for Highest Possible
Efficiency - up to 90% Efficient
n 2.6V to 5.5V input range
n Low operating supply current: 32µA
n Shutdown supply current: 0.1µA
n Thermal and short circuit protection
n Available in an 8-Pin MSOP Package
Applications
n Cellular Phones
n Pagers
n H/PC and P/PC Devices
n Portable Electronic Equipment
n Handheld Instrumentation
Typical Application Circuit
20044401
© 2002 National Semiconductor Corporation DS200444
www.national.com
1 page Typical Performance Characteristics
Unless
otherwise
specified:
CIN
=
10µF,
C1
=
1.0µF,
C2
=
1.0µF
COUT
=
10µF,
TA
=
25oC.
Capacitors
are
www.DataSheet4U.com
low-ESR multi-layer
ceramic capacitors (MLCC’s).
Output Voltage vs. Input Voltage:
LM2788-1.5 (1mA)
Output Voltage vs. Input Voltage:
LM2788-1.5 (120mA)
20044407
Output Voltage vs. Input Voltage:
LM2788-1.8 (1mA)
20044408
Output Voltage vs. Input Voltage:
LM2788-1.8 (120mA)
20044409
Output Voltage vs. Input Voltage:
LM2788-2.0 (1mA)
20044410
Output Voltage vs. Input Voltage:
LM2788-2.0 (120mA)
20044411
5
20044412
www.national.com
5 Page Application Information (Continued)
• Use short, wide traces to connect the external capacitors
to the LM2788 to minimize trace resistwanwcwe .DanadtainShdeuce-t4U.com
tance.
• Use a low resistance connection between ground and the
GND pin of the LM2788. Using wide traces and/or mul-
tiple vias to connect GND to a ground plane on the board
is most advantageous.
Figure 2 is a sample single-layer board layout that accom-
modates the LM2788 typical application circuit, as pictured
on the cover of this datasheet
Even under these peak power dissipation and ambient tem-
perature conditions, the junction temperature of the LM2788
is below the maximum operating rating of 125˚C.
As an additional note, the ambient temperature operating
rating range listed in the specifications is provided merely for
convenience. The LM2788 may be operated outside this
rating, so long as the junction temperature of the device
does not exceed the maximum operating rating of 125˚C.
Layout Guidelines
Proper board layout to accommodate the LM2788 circuit will
help to ensure optimal performance. The following guide-
lines are recommended:
• Place capacitors as close to the LM2788 as possible, and
preferably on the same side of the board as the IC.
20044424
FIGURE 2. Sample single-layer board layout of the
LM2788 Typical Application Circuit (Vias to a ground
plane, assumed to be present, are located in the
center of the LM2788 footprint.)
11 www.national.com
11 Page |
Páginas | Total 12 Páginas | |
PDF Descargar | [ Datasheet LM2788.PDF ] |
Número de pieza | Descripción | Fabricantes |
LM2780 | LM2780 Ultra-Low Ripple Switched Capacitor Voltage Inverter (Rev. C) | Texas Instruments |
LM2780 | Ultra-Low Ripple Switched Capacitor Voltage Inverter | National Semiconductor |
LM2781 | LM2781 Ultra-Low Ripple Switched Capacitor Voltage Inverter (Rev. B) | Texas Instruments |
LM2781 | Ultra-Low Ripple Switched Capacitor Voltage Inverter | National Semiconductor |
Número de pieza | Descripción | Fabricantes |
SLA6805M | High Voltage 3 phase Motor Driver IC. |
Sanken |
SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
Analog Devices |
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |