LM3875 Overture Audio Power Amplifier Series High-Performance 56W Audio Power Amplifier
LM3875 OvertureTM Audio Power Amplifier Series High-Performance 56W Audio Power Amplifier
The is a high-performance audio power amplifier capable of delivering 56W of continuous average power an 8 load with 0.1% THD+N from to 20kHz. The performance of the LM3875, utilizing its Self Peak Instantaneous Temperature (°Ke) (SPiKeTM) protection circuitry, puts in a class above discrete and hybrid amplifiers by providing an inherently, dynamically protected Safe Operating Area (SOA). SPiKe protection means that these parts are completely safeguarded at the output against overvoltage, undervoltage, overloads, caused by shorts to the supplies, thermal runaway, and instantaneous temperature peaks. The LM3875 maintains an excellent signal-to-noise ratio of greater than 95dB(min) with a typical low noise floor 2.0µV. It exhibits extremely low THD+N values 0.06% at the rated output into the rated load over the audio spectrum, and provides excellent linearity with an IMD (SMPTE) typical rating of 0.004%.
Features
56W continuous average output power into 8 100W instantaneous peak output power capability Signal-to-Noise Ratio > 95dB (min) Output protection from a short to ground or to the supplies via internal current limiting circuitry Output over-voltage protection against transients from inductive loads Supply under-voltage protection, not allowing internal biasing to occur when |V+| + |V-| 12V, thus eliminating turn-on and turn-off transients 11 lead TO-220 package Wide supply voltage range: |V+| + |V-| to 84V
Applications
Component or compact stereos Self-powered speakers Surround-sound amplifiers High-end stereo TVs
*Optional components dependent upon specific design requirements. Refer to the External Components Description section for a component function description.
FIGURE 1. Typical Audio Amplifier Application Circuit
OvertureTM and SPiKeTM are trademarks of National Semiconductor Corporation.
Top View Order Number or LM3875TF See NS Package Number TA11B for Staggered Lead Non-Isolated Package or TF11B for Staggered Lead Isolated Package
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage |V+| + |V-| (No Signal) Supply Voltage |V+| + |V-| (Input Signal) Common Mode Input Voltage Differential Input Voltage Output Current Power Dissipation (Note 3) ESD Susceptibility (Note 4) Junction Temperature (Note 5) Soldering Information T package (10 seconds) 94V 84V (V+ or V-) and |V+| + |V-| 80V 60V Internally Limited 150°C 260°C
Temperature Range TMIN TA TMAX Supply Voltage |V+| + |V-| to 84V
Note: Operation is guaranteed to 84V, however, distortion may be introduced from the SPiKe Protection Circuitry when operating above 70V if proper thermal considerations are not taken into account. Refer to the Thermal Considerations section for more information. (See SPiKe Protection Response)
Electrical Characteristics (Notes 1, 2) The following specifications apply for = -35V with = 8 unless otherwise specified. Limits apply for = 25°C.
LM3875 Symbol |V+| + |V-| **PO Peak PO THD + N **SR *I+ *VOS IB IOS Io *Vod *PSRR Parameter Power Supply Voltage Output Power (Continuous Average) Instantaneous Peak Output Power Total Harmonic Distortion Plus Noise Slew Rate (Note 9) Total Quiescent Power Supply Current Input Offset Voltage Input Bias Current Input Offset Current Output Current Limit Output Dropout Voltage Power Supply Rejection Ratio f 20 kHz 26 dB VIN = 1.414 Vrms, = 10 kHz Square-wave, 2 k VCM 0 mA VCM 0 mA VCM 0 mA VCM 0 mA |V+| = |V-| = 10V, ton = 10 ms, = 0V |V+-Vo-|, +100 mA |Vo-V-|, = -40V, Vcm to -20V, Vcm to -60V, Vcm 0 mA |V+| = |V-| = 60V |V+| = |V-| = 100 kHz, VIN = 50 mVrms IHF - A Weighting Filter RIN = 600 (Input Referred) THD = 0.1% (Max) = 1 kHz, = 20 kHz Conditions Typical (Note 6) Limit (Note Units (Limits) V (Min) V (Max) W (Min) W % V/µs (Min) mA (Max) mV (Max) µA (Max) µA (Max) A(Min) V (Max) V (Max)
Common Mode Rejection Ratio Open Loop Voltage Gain Gain-Bandwidth Product Input Noise
|