LMN/NOPB Texas Instruments Audio Amplifiers 5-W AUDIO POWER AMP datasheet, inventory, & pricing. LMN Datasheet, LMN National Semiconductor 5-Watt Audio Amplifier Datasheet, buy LMN. The LM is a power audio amplifier for consumer applica- tion In order to hold system cost to a minimum gain is internally fixed at 34 dB A unique input stage.

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Those shown in Figure 4 will normally be acceptable, or you can fabricate something yourself that makes good thermal contact with pins 3, 4, 5 and 10, 11, datasheef In order to hold system cost to a. The 8-pin version is shown first.

It’s important to understand that the LM is not an opamp, and none of the traditional opamp circuits can be applied. The only thing that even approaches being critical is the bypass cap.

The IC is useful for headphones, intercoms, portable radios etc. These range from a Wien bridge oscillator to intercoms and various others.

The impedance at both inputs is 50k, set by internal resistors. They can be run without a heatsink, but only for low power output, and care is needed to ensure the IC doesn’t overheat.

LM386, LM380 & LM384 Power Amplifiers

A unique input stage allows ground referenced input signals. It is possible to use a ground-plane on a PCB as a heatsink, but it’s not very effective and you need a lot of area to get what is still a sub-standard heatsink.

The tabs solder to the IC pins, and the underside of the xatasheet should be coated with heatsink compound to increase the thermal conductivity.

The power supply can be anything you have handy, including a battery. While a PCB would be handy, the cost of the board would be greater than the cost of the IC and other parts and it’s not worthwhile. Production processing does not necessarily include testing of all parameters. The load impedance needed is higher than any small speakers you can get, and you simply don’t build an amp using an LM if you dayasheet more than a few milliwatts.

If these pins are linked by a 10uF capacitor, the gain is 46dB.

LMN/NOPB – Texas Instruments – PCB Footprint & Symbol Download

These provide quite a bit of datasheeet, and lots of application circuits. Note that you cannot use aluminium because it can’t be soldered, but you may be able to use small copper tabs that are rivetted to an aluminium heatsink with heatsink compound between the two metals. C5 is a supply bypass cap, and it should be as close to the supply pins as possible. All trademarks are the property of their respective owners.


There’s no doubt that a small amp with similar performance can be made using an opamp dataaheet a couple of transistors, but the total cost and component count will be a great deal higher than will be the case with one of these ICs.

LMN datasheet, Pinout ,application circuits 5-W Audio Power Amplifier

The Zobel network at the output is needed dstasheet ensure stability when leads are attached, but even if the speaker is only a few millimetres away, don’t leave it out or the amp may oscillate.

Add a resistor and capacitor in series between pins 1 and 8 for intermediate gains.

That’s one of the reasons that the higher voltage ICs LM and LM have a higher gain than the LM – it’s simply to ensure full output swing before the input stage causes distortion. I don’t think I even need to say that this IC isn’t suitable for a subwoofer. The heatsink on the left is a commercial design which may be difficult to getmade by ‘Staver’ and is suggested for the LM – a higher voltage version of the LM Feel free to include a nF multilayer ceramic bypass cap as close to the supply pins as possible it’s not shown in the above drawings.

Input stage distortion will not occur until the input signal peak exceeds mV or so, and that’s far more than necessary given the gain of the IC.

Uses range from signal datzsheet, workshop monitor amps to listen to distortion residuals for exampleor just a simple project for the fun of it. None are anything special, and they are fairly low power the LM is only rated for mW into 8 ohms. The 8-pin version is only suitable for low power similar to the LMbut the pin version can be fitted with small heatsink ‘flags’ that allow it to provide up to 2. The 8-pin version of the LM is capable of around 1W, but that’s under ideal conditions.

Home – IC Supply – Link. Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

5-W Audio Power Amplifier

The datasheets don’t mention it, but there’s every chance that the ICs will oscillate if you fail to bypass the supply. The heatsink on the right can be fabricated from sheet copper, and I added two ‘spigots’ that can be inserted into the PCB to stabilise the heatsink against vibration. The supply voltage needs to be no more than 12V and the load impedance should not be less than 8 ohms. Production processing does not. Construction of any of these amps is non-critical, and Veroboard or similar is the way that most people would build one.


All pin numbers refer to the pin LM and the LM It should be easy enough to fabricate a suitable heatsink if you have some sheet copper available. These are certainly not hi-fi by any stretch of the imagination, but they are fine for a utility amplifier where a bit of distortion is unlikely to be a deal-breaker.

Commercial use is prohibited without express written authorisation from Rod Elliott. Products conform to specifications per the terms of the Texas Instruments standard warranty. It’s theoretically possible if you use a high supply voltage and a 16 or 32 ohm load, but that’s not recommended because device dissipation will be well in excess of that which the device can handle safely.

This makes the device easy to use in standard p-c layout. The suggested heatsink designs are shown below. The bypass cap C2 is optional as well, but if you don’t include it the power supply rejection is rather poor, so anything other than a battery supply may cause some hum. Distortion is acceptable at around 0.

Two are needed, one for each side of the IC. The LM can allegedly provide up to 5W, but don’t count on it. You can use either input for the signal, and simply ground the unused input. Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of.

Of the three types, the LM is the more popular. That means that the maximum input voltage will be around mV RMS sinewave at the onset of clipping. Uses include simple phonograph amplifiers, intercoms, line drivers, teaching machine outputs, alarms, ultrasonic drivers, TV sound systems, AM-FM radio and sound projector systems.