Features I 2C Control Interface I 2C programmable National 3D Audio I 2C controlled 32 step digital volume control (-59.5dB to +18dB) Three independent volume channels (Left, Right, Mono) Eight distinct output modes Small, 25–bump micro SMD packaging “Click and Pop” suppression circuitry Thermal shutdown protection Low shutdown current (0.1μA, typ) RF suppression Differential mono and stereo inputs Stereo input mux Description The LM4947 is an audio subsystem capable of efficiently delivering 500mW (Class D operation) of continuous average power into a mono 8Ω bridged-tied load (BTL) with 1% THD+N, 37mW (Class AB operation) power channel of continuous average power into stereo 32Ω single-ended (SE) loads with 1% THD+N, or an output capacitor-less (OCL) configuration with identical specification as the SE configuration, from a 3.3V power supply. The LM4947 has six input channels: one pair for a two-channel stereo signal, the second pair for a secondary two-channel stereo input, and the third pair for a differential single-channel mono input. Additionally, the two sets of stereo inputs may be configured as a single stereo differential input (differential left and differential right). The LM4947 features a 32-step digital volume control and eight distinct output modes. The digital volume control, 3D enhancement, and output modes are programmed through a two-wire I 2C compatible interface that allows flexibility in routing and mixing audio channels. The RF suppression circuitry in the LM4947 makes it well-suited for GSM mobile phones and other portable applications in which strong RF signals generated by an antenna (and long output traces) may couple audibly into the amplifier. The LM4947 is designed for cellular phones, PDAs, and other portable handheld applications. It delivers high quality output power from a surface-mount package and requires only eight external components in the OCL mode (two additional components in SE mode). Key Specification ■  THD+N at 1kHz, 500mW  into 8Ω BTL (3.3V) 1.0% (typ) ■  THD+N at 1kHz, 37mW  into 32Ω SE (3.3V) 1.0% (typ) ■  Single Supply Operation (VDD) 2.7 to 5.5V ■   I 2C Single Supply Operation 2.2 to 5.5V Applications Mobile Phones PDAs

Typical Application click for larger image	Connection Diagram click for larger image
Typical Performance click for larger image

Parameters Values Power @ 5V 8Ohms, 1% THD 1.19 Watt Speaker THD+N 0.03 % HP THD+N 0.02 % Speaker PSRR 79 dB HP PSRR 83 dB Audio Mux Yes Audio Mode Control I2C Supply Range +2.7 - +5.5 V Temperature Min -40 deg C Temperature Max 85 deg C Mono Analog Inputs 1 Stereo Analog Inputs 2 Digital Audio Ports 0 Additional Audio Features National 3D Loudspeaker Type Class D Loudspeaker Outputs 1 Headphone Type Virtual Ground

Datasheets

Title		Size	Date	Other Language
	LM4947 Mono Class D and Stereo Audio Sub-System with OCL Headphone Amplifier and National 3D	917 Kbytes	9-Nov-07

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM4947TL/NOPB RoHS Status	MICRO SMD	Full production Lead Time: 6 weeks	Distributor Region Qty DIGI-KEY Worldwide 0 MOUSER Worldwide 500 RS COMPONENTS Worldwide 75	$1.17 each at 1K+ pcs	reel of 250
LM4947TLX/NOPB RoHS Status	MICRO SMD	Full production Lead Time: 6 weeks	Distributor Region Qty DIGI-KEY Worldwide 0	$1.17 each at 1K+ pcs	reel of 3000

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM4947.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM4947 is located at RoHS Status.

Part Number(s) (NSID)	Description	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM4947TLEVAL	Mono Class D and Stereo Audio Subsystem with OCL Headphone Amplifier and National 3D	Full production	Distributor Region Qty DIGI-KEY Worldwide 0	$325.00 each	1
The LM4947 is an integrated stereo subsystem with a filterless monoClass D speaker amplifier and selectable output low noise headphone amplifier in a 25-bump micro SMD package. The LM4947 also features RF suppression circuitry and National 3D enhancement. The LM4947 is designed to meet the demands of mobile phones and other portable communication devices. It is capable of delivering 1.19W of average power into an 8 ohm load and 87 milliwatts of average power to a32 ohm load with less than 1% distortion (THD+N) from a 5V DC power supply. The LM4947TLEVAL is an evaluation board designed to ease evaluation and effort during the development of a circuit using the LM4947TL. The evaluation board comes with an I2C card and cable. It is an easy-to-use stand-alone board that requires power and GND, an I2C control signal, aninput signal and anoutput load. Software for the product can be downloaded from http://audio.national.com Features: Tiny micro SMD Very low iddq (12all outputs on at 5V) High output power (1.19W into 8ohms at 5V) 79dB PSRR 217Hz for speaker output 86dB PSRR 217Hz for headphone outputs 0.04% THD+N at 500mW for speaker output 0.01% THD+N at 30mW for OCL headphone outputs Applications: Mobile phones Portable devices, such as PMPs, GPS Contents: Fully Assembled LM4947TL Evaluation Board I2C interface card and cable Instructions for where to locate and download the datasheet Please note: Go to http://audio.national.com for more information on using the LM4947TL evaluation kit. Resources: Eval Board Digital Control Software

National Semiconductor follows the provisions of the Product Stewardship Guide for Customers (CSP-9-111C1) and Banned Substances and Materials of Interest Specification (CSP-9-111S2) for regulatory environmental compliance. Details may be found at: www.national.com/en/packaging/greennopb.html. Lead free products are RoHS compliant.

Lead Free product status is available through the search tool located here

Part Number(s) (NSID)	Weight (milligrams)	Type	Pins	MSL Rating	Peak Reflow	RoHS Status	CAD Symbols	Models	Package Marking Format
LM4947TL/NOPB	7.737	MICRO SMD	25	1	260	Detail	Download	N/A	XYTT I GH1
LM4947TLX/NOPB	7.737	MICRO SMD	25	1	260	Detail	Download	N/A	XYTT I GH1

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM4947.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM4947 is located at RoHS Status.

Design Tools

Title	Size	Date
Audio Amplifier Digital Control Interface Evaluation Board Software

CAD Symbols and Models Download LM4947 CAD Symbols

Models N/A

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM4947TL	CMOS7	0	21301	0	0	1584000	3	449464325
LM4947TLX	CMOS7	0	21301	0	0	1584000	3	449464325

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.

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM4947.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM4947 is located at RoHS Status.