LM is an adjustable voltage regulator IC used for shunt regulator, current regulator, and temperature controller. The LM LMC is a voltage regulator designed primar- ily for series regulator applications By itself it will supply output currents up to mA but external. Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. 2All trademarks are the property of their respective.
|Published (Last):||18 February 2009|
|PDF File Size:||12.54 Mb|
|ePub File Size:||15.36 Mb|
|Price:||Free* [*Free Regsitration Required]|
The LM is not discontinued at all, sold by TI in the millions, available from all electronic distributors and dirt cheap. This terminal is directly supplied from the supply when not connected to series pass transistor. As I found out and others did as datxsheet their consumer parts where a bit drifty within spec limitsprobably by a conversion to a new manufacturing process with not just improvements as a consequence.
The datasheet is not very instructive on this, but the floating regulator variants will fail to regulate when the load resistance becomes to high. There are only better ones with low voltage 10V and lessand they cost a lot more than a LM Input voltage goes up tp 40V constant, with 50V pulses allowed. Some extra bleeders are needed datashewt make falling edge output regulations fast enough.
Gate parasitic suppression resistors of a few Ohms are also a good idea. Naturally, it is frowned upon by a lot of designers that are just half as old. You are commenting using your Facebook account. Minimum dropout voltage is ca. You are commenting using your WordPress.
National Semiconductor – datasheet pdf
For finding the value of output voltage for this circuit you can use the formula below:. Especially when driving MOSFETs, you might need a bleeder resistor to make the falling edges fast enough for your needs. The LM is a classic, now available for 50 continuous years and still going strong.
Click here for a larger resolution picture … A lot of basic application circuits can be found in the LM datasheet.
Although the LM can dissipate a few mW and deliver up to mA, better vatasheet an external pass transistor to do the lm23 work and keep the regulator chip cool. Intolerant to missing or misdesigned compensation. Leave a Reply Cancel reply Enter your comment here This is due to the 7. Relying on a buried Zener low noise reference, it can compete with a lot of newer chips when it comes to stability it does have a long term stability rating in the datasheet, few new chips have that.
From a power supply manufacturer I read some email correspondence with TI tech support where he also claimed more drift in recent parts.
A schematic with all suggestions implemented can be seen at the bottom of this page. A schematic where all this has been km723 can be see below: First, ST went out of the LM business. To use dstasheet IC for the different range of required output voltage, you can proceed with various circuits available in LM datasheet with having your needed output range.
But this IC is specially designed for series regulator application. If you need to regulate lower voltages, the LM chip itself needs a separate power input at 10V minimum. If you have a heavily overcompensated i.
TL — Programmable Reference Voltage. This also acts as a soft start feature. After some ping-pong TI recommended the MIL-spec part and guaranteed that this would be free from drift. Silence or no reply. You can tailor the frequency response to your application but you also have to do that because there is no internal compensation. Click here for a larger resolution picture …. On a transistor level, you can see some design tricks by the legendary Bob Widlar: If we pragmatically summarize the pros and cons of this methusalem, we end up with something like this:.
Its comparing apples and oranges. No microscopic SMD cases available. Current limiting sensitive to overload.
Notify me of new comments via email. The LM values translate to about 0. There is even an obsolete 80V version, the LCB. One of the best low noise regulators even today when hooked up properly. For getting an output voltage range from 2v to 7v you can use the circuit below, which is a Basic Voltage Regulator circuit using LM voltage regulator IC. So, in case you have decided for an LM to make a good power supply, there are some rules of thumb that will make your life easier:.
The performance of an LM is not bad at all, especially for noise and long term stability.
I added a reference study that compares voltage regulator noise. Not a very high PSRR.
A Collection of Proper Design Practices using the LM723 IC Regulator
Try with different output voltages, load currents and input voltages. Fill in your details below or click an icon to log in: LM is an adjustable voltage regulator IC used for shunt regulator, current regulator, and temperature controller.
Which comparable ICs are so much better now?