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LM48821, LM48821TLEVAL
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SNAS354A – JUNE 2007 – REVISED MAY 2013
LM48821
Direct Coupled, Ultra Low Noise, 52mW
Differential Input Stereo Headphone Amplifier with I2C Volume Control
Check for Samples: LM48821, LM48821TLEVAL
FEATURES
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•2 Ground Referenced Outputs • Differential Inputs • I2C Volume and Mode Controls • Available in Space-Saving DSBGA Package • Ultra Low Current Shutdown Mode • Advanced Output Transient Suppression
Circuitry Eliminates Noises During Turn-On and Turn-Off Transitions • 2.0V to 4.0V Operation (PVDD and SVDD) • 1.8 to 4.0V Operation (I2CVDD) • No Output Coupling Capacitors, Snubber Networks, Bootstrap Capacitors, or GainSetting Resistors Required
APPLICATIONS
• Notebook PCs • Desktop PCs • Mobile Phones • PDAs • Portable Electronic Devices • MP3 Players
KEY SPECIFICATIONS
• Improved PSRR at 217Hz: 82dB (typ) • Stereo Output Power at VDD = 3V, RL = 16Ω,
THD+N = 1%: 52mW (typ) • Mono Output Power at VDD = 3V, RL = 16Ω,
THD+N = 1%: 93mW (typ) • Shutdown current: 0.1μA (typ)
DESCRIPTION
With its directly-coupled output technology, the LM48821 is a variable gain audio power amplifier capable of delivering 52mWRMS per channel into a 16Ω single-ended load with less than 1% THD+N from a 3V power supply. The I2C volume control has a range of –76dB to 18dB.
The LM48821's Tru-GND technology utilizes advanced charge pump technology to generate the LM48821’s negative supply voltage. This eliminates the need for output-coupling capacitors typically used with single-ended loads.
Boomer audio power amplifiers were designed specifically to provide high quality output power with a minimal amount of external components. The LM48821 does not require output coupling capacitors or bootstrap capacitors, and therefore, is ideally suited for mobile phone and other low voltage applications where minimal power consumption is a primary requirement.
The LM48821 incorporates selectable low-power consumption shutdown and channel select modes.
The LM48821 contains advanced output transient suppression circuitry that eliminates noises which would otherwise occur during turn-on and turn-off transitions.
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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.
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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 © 2007–2013, Texas Instruments Incorporated
LM48821, LM48821TLEVAL
SNAS354A – JUNE 2007 – REVISED MAY 2013
Typical Application
0.47 PF
IN A-
0.1 PF
VDD
4.7 PF
0.1 PF
PVDD SVDD
0.47 PF
IN A+
-
+
0.47 PF
IN B+
0.47 PF
IN B-
SCL
I2C Digitally
Digital
SDA
Controlled
Control System
I2CVDD
Analog Volume Control Interface
Bias Control
+ -
Charge Pump
VOA SGND VOB
CCP-
CCP+
VSS
PGND
4.7 PF
4.7 PF
Figure 1. Typical Audio Amplifier Application Circuit
Connection Diagram
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IN A-
IN B-
I2CVDD
PVDD
3
IN A+
IN B+
SDA
CCP+
2
SGND
VOB
SCL
PGND
1
SVDD
VOA
VSS
CCP-
A
B
C
D
Figure 2. DSBGA - Top View See YZR0016 Package
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Copyright © 2007–2013, Texas Instruments Incorporated
Product Folder Links: LM48821 LM48821TLEVAL
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Pin Designator A1 A2 A3 A4 B1 B2 B3 B4 C1 C2 C3 C4 D1 D2 D3 D4
LM48821, LM48821TLEVAL
SNAS354A – JUNE 2007 – REVISED MAY 2013
PIN DESCRIPTIONS
Pin Name
Pin Function
SVDD SGND
Signal power supply input Signal ground
IN A+
Left non-inverting input
IN A-
Left inverting input
VOA VOB IN B+
Left output Right output Right non-inverting input
IN B-
Right inverting input
VSS SCL SDA I2CVDD CCPPGND
DC to DC converter output I2C serial clock input I2C serial data input I2C supply voltage input DC to DC converter flying capacitor inverting input Power ground
CCP+ PVDD
DC to DC converter flying capacitor non-inverting input DC to DC converter power supply input
Copyright © 2007–2013, Texas Instruments Incorporated
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LM48821, LM48821TLEVAL
SNAS354A – JUNE 2007 – REVISED MAY 2013
www.ti.com
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates.
Absolute Maximum Ratings (1)(2)(3)
Supply Voltage
4.5V
Storage Temperature
−65°C to +150°C
Input Voltage Power Dissipation (4) ESD Susceptibility (5) ESD Susceptibility (6)
−0.3V to VDD +0.3V Internally Limited 2000V 200V
Junction Temperature
150°C
Thermal Resistance θJA (typ) - (DSBGA) (4)
105°C/W
.