|
|
PDF LM4865MM Data sheet ( Hoja de datos )
| Número de pieza | LM4865MM | |
| Descripción | 750 mW Audio Power Amplifier with DC Volume Control and Headphone Switch | |
| Fabricantes | National Semiconductor | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de LM4865MM (archivo pdf) en la parte inferior de esta página. Total 9 Páginas | ||
|
No Preview Available !
December 1999
LM4865
750 mW Audio Power Amplifier with DC Volume Control
and Headphone Switch
General Description
The LM4865 is a mono bridged audio power amplifier with
DC volume control, capable of delivering 750 mW of continu-
ous average power into an 8Ω load with less than 1% THD
from a 5V power supply. Switching between bridged speaker
mode and headphone (single ended) mode is accomplished
via a headphone sense pin. In addition, LM4865 is set into
low current consumption shutdown mode (0.7 µA typical) by
lowering the DC Vol/SD pin to below 0.3V.
Boomer audio power amplifiers are designed specifically to
provide high power audio output, with quality sound, from a
low supply voltage source while requiring the minimal
amount of external components.
Applications
n GSM phones and accessories, DECT, office phones
n Hand held radio
n Other portable audio devices
Key Specifications
n PO at 1.0% THD+N into 8Ω (SOP): 750 mW (typ)
n PO at 10% THD+N into 8Ω (SOP): 1W (typ)
n Shutdown Current: 0.7 µA (typ)
Features
n DC volume control
n Headphone amplifier mode
n “Click and pop” suppression
n Shutdown control when volume control pin is low
n Thermal shutdown protection
Typical Application
Connection Diagram
MSOP, SOP Package
DS101025-1
FIGURE 1. Typical Audio Amplifier
Application Circuit
DS101025-2
Top View
Order Number LM4865M, LM4865MM
See NS Package Number M08A, MUA08A
BOOMER™ is a trademark of National Semiconductor Corporation.
© 1999 National Semiconductor Corporation DS101025
www.national.com
1 page  
Typical Performance Characteristics (Continued)
THD+N vs Output Power
THD+N vs Output Power
THD+N vs Output Power
DS101025-23
Output Power vs Load Resistance
DS101025-24
DS101025-28
Clipping Voltage vs Supply Voltage
Output Power vs Supply Voltage
DS101025-29
Output Power vs Supply Voltage
DS101025-30
Supply Current vs Supply Voltage
DS101025-31
DS101025-32
Application Information
BRIDGE CONFIGURATION EXPLANATION
As shown in Figure 1 , the LM4865 has two operational am-
plifiers internally, allowing for a few different amplifier con-
figurations. The first amplifier’s gain is DC voltage controlled,
while the second amplifier is internally fixed in a unity-gain,
inverting configuration. The closed-loop gain of the first am-
plifier is set by an external DC voltage (refer to (Figure 1),
while the second amplifier’s gain is fixed by the two internal
20 kΩ resistors.
Figure 1 shows that the output of amplifier one serves as the
input to amplifier two which results in both amplifiers produc-
ing signals identical in magnitude, but out of phase 180˚.
DS101025-33
By driving the load differentially through outputs VO1 and
VO2, an amplifier configuration commonly referred to as
“bridged mode” is established. Bridged mode operation is
different from the classical single-ended amplifier configura-
tion where one side of its load is connected to ground.
A bridge amplifier design has a few distinct advantages over
the single-ended configuration, as it provides differential
drive to the load, thus doubling output swing for a specified
supply voltage. Four times the output power is possible as
compared to a single-ended amplifier under the same condi-
tions. This increase in attainable output assumes that the
amplifier is not current limited or clipped. In order to choose
an amplifier’s closed-loop gain without causing excessive
clipping, please refer to the Audio Power Amplifier Design
section.
5 www.national.com
5 Page | ||
| Páginas | Total 9 Páginas | |
| PDF Descargar | [ Datasheet LM4865MM.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| LM4865M | 750 mW Audio Power Amplifier with DC Volume Control and Headphone Switch | National Semiconductor |
| LM4865MM | 750 mW Audio Power Amplifier with DC Volume Control and Headphone Switch | 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 |