LM386 LM386 Low Voltage Audio Power Amplifier Literature Number: SNAS545A
LM386 Low Voltage Audio Power Amplifier General Description Features The LM386 is a power amplifier designed for use in low voltage consumer applications. The gain is internally set to 20 to keep external part count low, but the addition of an external resistor and capacitor between pins 1 and 8 will increase the gain to any value from 20 to 200. The inputs are ground referenced while the output automatically biases to one-half the supply voltage.
LM386 Absolute Maximum Ratings (Note 2) Dual-In-Line Package Soldering (10 sec) +260˚C Small Outline Package (SOIC and MSOP) Vapor Phase (60 sec) +215˚C Infrared (15 sec) +220˚C See AN-450 “Surface Mounting Methods and Their Effect on Product Reliability” for other methods of soldering surface mount devices.
LM386 Application Hints GAIN CONTROL INPUT BIASING To make the LM386 a more versatile amplifier, two pins (1 and 8) are provided for gain control. With pins 1 and 8 open the 1.35 kΩ resistor sets the gain at 20 (26 dB). If a capacitor is put from pin 1 to 8, bypassing the 1.35 kΩ resistor, the gain will go up to 200 (46 dB). If a resistor is placed in series with the capacitor, the gain can be set to any value from 20 to 200.
LM386 Typical Performance Characteristics Quiescent Supply Current vs Supply Voltage Power Supply Rejection Ratio (Referred to the Output) vs Frequency Peak-to-Peak Output Voltage Swing vs Supply Voltage DS006976-5 DS006976-13 DS006976-12 Voltage Gain vs Frequency Distortion vs Frequency DS006976-15 DS006976-14 Device Dissipation vs Output Power — 4Ω Load Device Dissipation vs Output Power — 8Ω Load DS006976-17 www.national.
LM386 Typical Applications Amplifier with Gain = 20 Minimum Parts Amplifier with Gain = 200 DS006976-4 DS006976-3 Amplifier with Gain = 50 Low Distortion Power Wienbridge Oscillator DS006976-6 DS006976-7 Amplifier with Bass Boost Square Wave Oscillator DS006976-8 DS006976-9 5 www.national.
LM386 Typical Applications (Continued) Frequency Response with Bass Boost DS006976-10 AM Radio Power Amplifier DS006976-11 Note 4: Twist Supply lead and supply ground very tightly. Note 5: Twist speaker lead and ground very tightly. Note 6: Ferrite bead in Ferroxcube K5-001-001/3B with 3 turns of wire. Note 7: R1C1 band limits input signals. Note 8: All components must be spaced very closely to IC. www.national.
LM386 Physical Dimensions inches (millimeters) unless otherwise noted SO Package (M) Order Number LM386M-1 NS Package Number M08A 7 www.national.
LM386 Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 8-Lead (0.118” Wide) Molded Mini Small Outline Package Order Number LM386MM-1 NS Package Number MUA08A www.national.
LM386 Low Voltage Audio Power Amplifier Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Dual-In-Line Package (N) Order Number LM386N-1, LM386N-3 or LM386N-4 NS Package Number N08E LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1.
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