lm4895 National Semiconductor Corporation, lm4895 Datasheet

no-image

lm4895

Manufacturer Part Number
lm4895
Description
1 Watt Fully Differential Audio Power Amplifier With Shutdown Select And Fixed 6db Gain
Manufacturer
National Semiconductor Corporation
Datasheet

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
lm4895LD
Manufacturer:
NS
Quantity:
21
Part Number:
lm4895LD
Manufacturer:
NSC
Quantity:
55
Part Number:
lm4895LD
Manufacturer:
NS
Quantity:
26
Part Number:
lm4895LD
Manufacturer:
PERICOM
Quantity:
45
Part Number:
lm4895LD
Manufacturer:
NS/国半
Quantity:
20 000
Part Number:
lm4895MM
Manufacturer:
NSC
Quantity:
800
Part Number:
lm4895MM
Manufacturer:
NS/国半
Quantity:
20 000
Part Number:
lm4895MMX
Manufacturer:
NS/国半
Quantity:
20 000
© 2002 National Semiconductor Corporation
LM4895
1 Watt Fully Differential Audio Power Amplifier With
Shutdown Select and Fixed 6dB Gain
General Description
The LM4895 is a fully differential audio power amplifier
primarily designed for demanding applications in mobile
phones and other portable communication device applica-
tions. It is capable of delivering 1 watt of continuous average
power to an 8Ω load with less than 1% distortion (THD+N)
from a 5V
Boomer audio power amplifiers were designed specifically to
provide high quality output power with a minimal amount of
external components. The LM4895 does not require output
coupling capacitors or bootstrap capacitors, and therefore is
ideally suited for mobile phone and other low voltage appli-
cations where minimal power consumption is a primary re-
quirement.
The LM4895 features a low-power consumption shutdown
mode. To facilitate this, Shutdown may be enabled by either
logic high or low depending on mode selection. Driving the
shutdown mode pin either high or low enables the shutdown
select pin to be driven in a likewise manner to enable Shut-
down. Additionally, the LM4895 features an internal thermal
shutdown protection mechanism.
The LM4895 contains advanced pop & click circuitry which
eliminates noises which would otherwise occur during
turn-on and turn-off transitions.
The LM4895 has an internally fixed gain of 6dB.
Typical Application
Boomer
®
is a registered trademark of National Semiconductor Corporation.
DC
power supply.
FIGURE 1. Typical Audio Amplifier Application Circuit
DS200232
Key Specifications
Features
n Fully differential amplification
n Internal-gain-setting resistors
n Available in space-saving packages micro SMD, MSOP
n Ultra low current shutdown mode
n Can drive capacitive loads up to 500 pF
n Improved pop & click circuitry eliminates noises during
n 2.2 - 5.5V operation
n No output coupling capacitors, snubber networks or
n Shutdown high or low selectivity
Applications
n Mobile phones
n PDAs
n Portable electronic devices
j
j
j
j
and LLP
turn-on and turn-off transitions
bootstrap capacitors required
Improved PSRR at 217Hz
Power Output at 5.0V & 1% THD
Power Output at 3.3V & 1% THD
Shutdown Current
20023201
October 2002
400mW(typ.)
www.national.com
0.1µA(typ.)
1.0W(typ.)
80dB

Related parts for lm4895

lm4895 Summary of contents

Page 1

... Additionally, the LM4895 features an internal thermal shutdown protection mechanism. The LM4895 contains advanced pop & click circuitry which eliminates noises which would otherwise occur during turn-on and turn-off transitions. The LM4895 has an internally fixed gain of 6dB. Typical Application FIGURE 1. Typical Audio Amplifier Application Circuit Boomer ® ...

Page 2

... Bump micro SMD Package 20023236 Top View Order Number LM4895IBP See NS Package Number BPA09CDB LLP Package 20023235 Top View Order Number LM4895LD See NS Package Number LDA10B Mini Small Outline (MSOP) Package 20023223 Top View Order Number LM4895MM See NS Package Number MUB10A 2 ...

Page 3

... and 8Ω load unless otherwise specified. Limits apply for T DD Conditions GND shutdown THD = 1% (max kHz LM4895LD 4Ω (Note 11) L LM4895 8Ω 0.4 Wrms 1kHz 200mV sine p-p ripple f = 217Hz (Note 9) f =1kHz (Note 9) ...

Page 4

... Note 8: For micro SMD only, shutdown current is measured in a Normal Room Environment. Exposure to direct sunlight will increase I Note 9: Unterminated input. Note 10: 10Ω terminated input. Note 11: When driving 4Ω loads from a 5V supply, the LM4895LD must be mounted to a circuit board. External Components Description Components 1 ...

Page 5

... PWR = 400mW DD L THD+N vs Frequency 3V, 4Ω and PWR = 225mW DD L (Continued) Power Derating Curve 20023211 V = 3V, 8Ω 20023213 V = 2.6V, 8Ω 20023231 5 LM4895LD 20023212 THD+N vs Frequency , and PWR = 250mW L 20023230 THD+N vs Frequency , and PWR = 150mW L 20023232 www.national.com ...

Page 6

Typical Performance Characteristics Non-LD Specific Characteristics THD+N vs Frequency 2.6V, 4Ω and PWR = 150mW DD L THD+N vs Output Power 3V, 8Ω THD+N vs Output Power ...

Page 7

Typical Performance Characteristics Non-LD Specific Characteristics Power Supply Rejection Ratio (PSRR) V Input 10Ω Terminated Power Supply Rejection Ratio (PSRR) V Input 10Ω Terminated Output Power vs Supply Voltage (Continued Power Supply Rejection Ratio (PSRR 20023275 ...

Page 8

Typical Performance Characteristics Non-LD Specific Characteristics Power Dissipation vs Output Power Power Dissipation vs Output Power Supply Current vs Shutdown Voltage Shutdown Low www.national.com (Continued) Power Dissipation vs 20023281 20023283 Supply Current vs Shutdown Voltage 20023285 8 Output Power 20023282 ...

Page 9

Typical Performance Characteristics Non-LD Specific Characteristics Clipping (Dropout) Voltage vs Supply Voltage Power Derating Curve Input CMRR vs Frequency (Continued) Open Loop Frequency Response 20023287 20023289 Input CMRR vs Frequency 20023291 9 20023288 Noise Floor 20023290 20023292 www.national.com ...

Page 10

Typical Performance Characteristics Non-LD Specific Characteristics PSRR vs DC Common-Mode Voltage THD vs Common-Mode Voltage www.national.com (Continued) DC Common-Mode Voltage 20023293 Common-Mode Voltage 20023295 10 PSRR vs 20023294 THD vs 20023296 ...

Page 11

... The DD share the same PCB layer, a nominal 2.5in necessary for 5V operation with a 4Ω load. Heatsink areas not placed on the same PCB layer as the LM4895 should be 2 5in (min) for the same supply voltage and load resistance. The last two area recommendations apply for 25˚C ambient temperature. In all circumstances and conditions, the junc- tion temperature must be held below 150˚ ...

Page 12

... A JA designer maximum flexibility in device use, as the Shutdown Mode pin may simply be tied permanently to either V GND to set the LM4895 as either a ’shutdown-high’ device the system A a ’shutdown-low’ device, respectively. The device may then be placed into shutdown mode by toggling the Shutdown Select pin to the same state as the Shutdown Mode pin. For simplicity’ ...

Page 13

... Physical Dimensions inches (millimeters) unless otherwise noted X1 = 1.336 9-Bump micro SMD Order Number LM4895IBP NS Package Number BPA09CDB ± ± 0. 1.361 0. 0.850 13 ± 0.10 www.national.com ...

Page 14

... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted (Continued) LLP Order Number LM4895LD NSPackage Number LDA10B 14 ...

Page 15

... National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. inches (millimeters) unless otherwise noted (Continued) Mini Small Outline (MSOP) Order Number LM4895MM NSPackage Number MUB10A 2. A critical component is any component of a life ...

Related keywords