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Details, datasheet, quote on part number:LM4664
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Datasheet text preview:
LM4664 Filterless High Efficiency 1.1W Switching Audio Amplifier
March 2004
LM4664 Filterless High Efficiency 1.1W Switching Audio Amplifier
General Description
The LM4664 is a fully integrated single-supply high efficiency switching audio amplifier. It features an innovative modulator that eliminates the LC output filter used with typical switching amplifiers. Eliminating the output filter reduces parts count, simplifies circuit design, and reduces board area. The LM4664 processes analog inputs with a delta-sigma modulation technique that lowers output noise and THD when compared to conventional pulse width modulators. The LM4664 is designed to meet the demands of mobile phones and other portable communication devices. Operating on a single 3V supply, it is capable of driving 8 transducer loads at a continuous average output of 425mW with less than 1%THD+N. Its flexible power supply requirements allow operation from 2.7V to 5.5V. The LM4664 has high efficiency with an 8 transducer load compared to a typical Class AB amplifier. With a 3V supply, the IC's efficiency for a 100mW power level is 74%, reaching 84% at 425mW output power. The LM4664 features a low-power consumption shutdown mode. Shutdown may be enabled by driving the Shutdown pin to a logic low (GND). The LM4664 has fixed selectable gain of either 6dB or 12dB. The LM4664 has short circuit protection against a short from the outputs to VDD, GND, or across the outputs.
Key Specifications
j Efficiency at 3V, 100mW into 8 transducer 74% (typ) j Efficiency at 3V, 425mW into 8 transducer 84% (typ) j Efficiency at 5V, 1W into 8 transducer j Total quiescent power supply current j Total shutdown power supply current j Single supply range
86% (typ) 3.5mA (typ) 0.4µA (typ) 2.7V to 5.5V
Features
n n n n n n n n No output filter required for inductive transducers Selectable gain of 6dB or 12dB Very fast turn on time: 7ms (typ) Minimum external components "Click and pop" suppression circuitry Micro-power shutdown mode Short circuit protection Available in space-saving micro SMD package
Applications
n Mobile phones n PDAs n Portable electronic devices
Typical Application
200960G5
FIGURE 1. Typical Audio Amplifier Application Circuit
Boomer ® is a registered trademark of National Semiconductor Corporation.
© 2004 National Semiconductor Corporation
DS200960
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LM4664
Connection Diagrams
9 Bump micro SMD Package micro SMD Marking
200960K1
Top View X -- Date Code T -- Die Traceability G -- Boomer Family E4 LM4664ITL
20096036
Top View Order Number LM4664ITL, LM4664ITLX See NS Package Number TLA09AAA
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LM4664
Absolute Maximum Ratings (Notes 1, 2)
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage (Note1) Storage Temperature Voltage at Any Input Pin Power Dissipation (Note 3) ESD Susceptibility (Note 4) ESD Susceptibility (Note 5) Junction Temperature (TJ) 6.0V -65°C to +150°C VDD + 0.3V V GND - 0.3V Internally Limited 7.0kV 250V 150°C
Thermal Resistance JA (micro SMD) Soldering Information See AN-1112 "microSMD Wafers Level Chip Scale Package." 220°C/W
Operating Ratings (Note 2)
Temperature Range TMIN TA TMAX Supply Voltage -40°C TA 85°C 2.7V VDD 5.5V
Electrical Characteristics VDD = 3V (Notes 1, 2) The following specifications apply for VDD = 3V and RL = 15µH + 8 + 15µH unless otherwise specified. Limits apply for TA = 25°C.
LM4664 Symbol IDD ISD VSDIH VSDIL VGSIH VGSIL AV AV VOS TWU Po THD+N RIN Parameter Quiescent Power Supply Current Shutdown Current Shutdown Voltage Input High Shutdown Voltage Input Low Gain Select Input High Gain Select Input Low Closed Loop Gain Closed Loop Gain Output Offset Voltage Wake-up Time Output Power Total Harmonic Distortion+Noise Differential Input Resistance THD = 1% (max), f = 1kHz PO = 100mWRMS; fIN = 1kHz VGain VGain
Select Select
Conditions VIN = 0V, No Load VIN = 0V, RL = 15µH + 8 + 15µH VSD = GND (Note 9)
Typical (Note 6) 3.50 3.75 0.4 1.0 0.8 1.0 0.8
Limit (Notes 7, 8) 5.0 2.0 1.4 0.4 1.4 0.4
Units (Limits) mA mA (max) µA (max) V (min) V (max) V (min) V (max) dB dB
VGain VGain
Select Select
= VDD = GND
6 12 10 7 425 0.35 90 60 56 (f = 217Hz) 65 (f = 217Hz) 41 83 125 25
mV (max) ms mW % k k dB dB dB dB µV
= VDD = GND
PSRR
Power Supply Rejection Ratio
VRipple = 100mVRMS sine wave Inputs terminated to GND VRipple = 100mVRMS sine wave POUT = 10mW,1kHz VRipple = 100mVRMS, fRipple = 217Hz PO = 400mWRMS; A-Weighted Filter A-Weighted filter, Vin = 0V
CMRR SNR eOUT
Common Mode Rejection Ratio Signal to Noise Ratio Output Noise
3
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