LM386低電壓音頻功率放大器的原理與典型應(yīng)用電路

1、LM386低電壓音頻功率放大器的原理與典型應(yīng)用電路圖一、特性原理The LM386 is a power amplifier designed for use in low voltage consumer applications. The gain is intern ally set to 20 to keep exter nal part count low, but the additi on of an exter nal resistor and capacitor betwee n pins 1 and 8 will in crease the gain to any valu

2、e from 20 to 200。The in puts are ground referenced while the output automatically biases to on e-half the supply voltage.The quiesce nt power drain is only 24 milliwatts whe n operat ing from a 6 volt supply, mak ing the LM386 ideal for battery operation。LM386是美國國家半導(dǎo)體公司生產(chǎn)的音頻功率放大器，主要應(yīng)用于低電壓消費類產(chǎn)品。為使 外圍

3、元件最少，電壓增益內(nèi)置為20。但在1腳和8腳之間增加一只外接電阻和電容，便可將電壓增益調(diào)為任意值，直至 200。輸入端以地位參考，同時輸出端被自動偏置到電源電壓的一半，在6V電源電壓下，它的靜態(tài)功耗僅為 24mW，使得LM386特別適用于電池供電的場合。益入入地岀曲路益 熾輸輸接輸電為増 : : 巴* :I 2 3 4 5 6 7 8LM386的封裝形式有塑封 8引線雙列直插式和貼片式。貼片封裝形式SOPLM386 特性(Features):*靜態(tài)功耗低，約為 4mA,可用于電池供電。*工作電壓范圍寬，4-12V or 5-18V。*外圍元件少。*電壓增益可調(diào)，20-200。*低失真度。黑號4

4、狀態(tài)*(°C)*價格【美元）1=Quantity*封裝I引黑 TLM336M-1ACTIVE0 to 700,2711kuSCIC (D)| 8LM386MJTOPBACTIVE0 to 700 27 | 1kuSCIC (D)| 8LM386MMX-1/NOPBACTIVE0 to 700 27 I 1kuVSSOP (DGK)I8LMJ86MX-1/NOPBACTIVE0 to 700 27 | 1kuSOIC (D)| SLM386NACTIVE0 to 700 27 I 1kuPDIP (P)| SLJM386N-1ACTIVE0 to 700 27 | 1kuPDIP (P)| SLM386N-1/NOPBACTIVE0 to 700 27 | 1kuPDIP (P)| 8LM386N-3ACTIVE0 to 70031 | 1kuPDIP (P)| 8LM386N-3/NOPBACTIVE0 10 70031 | 1kuPDIP (P)| 8LM386NACTIVEG to 700.31 11kuPDIP (P)| 8LM396N4/NOPSACTIVE0 to 700.31 | 1kuPDIP (P)| 8二、典型應(yīng)用電路圖1、LM386應(yīng)用電路圖之增益=2