The following circuits show some of the basic uses of the lm317 lm338 lm350 series of voltage regulators when configured as a current regulator or constant current source ccs. In addition to excellent line and load regulation, with full overload. Ic lm338 application circuits homemade circuit projects. Lm317 lm338 lm350 voltage regulator calculator and. Changes in output voltage due to heating effects are covered under the specifications for thermal regulation. Threeterminal 5 a adjustable voltage regulators, lm338 datasheet, lm338 circuit, lm338 data sheet. The lm8, lm238, lm338 are packaged in standard steel to3 transistor package. The lm317 lm338 lm350 family of adjustable 3terminal positive voltage regulators can take a input of 3 to 40 volts dc and provide a regulated voltage over a 1.
You dont want to use too high an input voltage as the excess will need to be dissipated as heat through the regulator. Lm8 and lm338 5amp adjustable regulators datasheet rev. So, lets look into how to use this ic as a variable voltage regulator. Lm8 and lm338 5amp adjustable regulators datasheet. Since the regulator is floating and sees only the inputtooutput differential voltage, supplies of several hundred volts can be regulated as long as the maximum input to input differential is not exceeded. I am building two of these, with one slotting into my main power station, the powerstation2. Lmk datasheetpdf national semiconductor ti when external capacitors are used with a voltage regulator lm338, may be necessary to use protection diodes to prevent the capacitors from discharging through low current lm33k into the voltage regulator. Say we have a pc smps that supplies 15a at 12v rail,would lm338 current regulator work if a 10w led requires 12v and i want to drive it at 700ma. The internal voltage reference is trimmed to less than 1%, enabling a very tight output voltage. Lm338t datasheetpdf 1 page national semiconductor ti. Lm338ksteel old version datasheet lm8 lm338 5amp adjustable regulators. Careful circuit design has resulted in outstanding load andline regulation comparable.
Lm8 lm338 5amp adjustable regulators datasheet catalog. They are exceptionally easy touse and require only 2 resistors to set the output voltage. Lm338 datasheet pdf, lm338 data sheet, lm338, lm338. The other one i am using to create a portable power station for my desk. Lm338 datasheet adjustable power supply 5a and 10a. For this weeks project i have built a 5 amp variable voltage regulator using an lm338 serial regulator.
Although the lmm350 is very short in duration, there is enough energy to damage parts of the regulator ic. Voltage regulator the lt8a series of adjustable regulators provide 5a output current over an output voltage range of 1. Lm338 datasheet pdf the lmlmlm are adjustable 3terminal positive voltage regulators capable of supplying in excess of 5a over a. When external capacitors are used with a voltage regulator it may be necessary to use protection diodes to prevent the capacitors from discharging through low current points into the voltage regulator. Lm317d lm317, ncv317 voltage regulator adjustable output, positive 1. Lm338 datasheet 5amp adjustable regulators national, lm338k datasheet, lm338t datasheet, lm338 pdf, lm338 pinout, lm338 schematic, lm338 equivalent. Lm8 lm338 5amp adjustable regulators general description the lm8 series of adjustable 3terminal positive voltage regulators is capable of supplying in excess of 5a over a 1. Lm8 lm338 5amp adjustable regulators generaldescription the lm8 series of adjustable 3terminal positive voltage regulators is capable of supplying in excess of 5a over a 12v to 32v output range they are exceptionally easy to use and require only 2 resistors to set the output voltage careful circuit design has resulted in outstanding load and. Lm317 is a 3terminal regulator ic and it is very simple to use. This voltage regulator is exceptionally easy to use and requires only two external resistors to set the output voltage. So, if you are looking for a variable voltage regulator to set voltage between 1. Lm8 lm238 lm338 threeterminal 5 a adjustable voltage regulators features guaranteed 7 a peak output current guaranteed 5 a output current adjustable output down to 1. Lm338 datasheet, lm338 datasheets, lm338 pdf, lm338 circuit. Most h metal can, j ceramic, and k metal can packages from analog devices are obsolete the lt8a series of adjustable regulators provide 5a output current over an output voltage range of 1.
Semelab 5 amp positive adjustable voltage regulator,alldatasheet, datasheet, datasheet search site for electronic components and semiconductors, integrated circuits, diodes, triacs, and other semiconductors. Lm317 lm338 lm350 current regulator calculator and. Careful circuit design has resulted in outstanding. Lm317 linear integrated circuit 1 3terminal 1a positive adjustable voltage regulator description the contek lm317 is an adjustable 3terminal positive voltage regulator, designed to supply more than 1. The minimum load for the more expensive lm8 is 5ma when the input voltage is fairly high. Last update 6 january submitted by admin on 21 october the lm voltage regulators can provide. Device information1 part number package body size nom lm8 tocan 2 25. Can current be fixed to 700ma using lm338 current regulator. They are exceptionally easy to use and require only 2 resistors to set the output voltage. Lm8lm3385amp adjustable regulatorsgeneral descriptionthe lm8 series of adjustable 3terminal positive voltageregulators is capable of supplying in excess of 5a over a1. Lm8 lm238 lm338 threeterminal 5 a adjustable voltage regulators features i guaranteed, disconnected.
Lm338 datasheet 5amp adjustable regulators national. Solid tantalum capacitors can be used on the voltage output to improve the ripple rejection of the voltage regulator. Stmicroelectronics, alldatasheet, datasheet, datasheet search site for electronic components and semiconductors, integrated circuits, diodes, triacs, and other semiconductors. As said earlier the ic has 3 pins, in which the input voltage is supplied to pin3 vin. Lm338t datasheet pdf lmt datasheet, lm 5a adjustable positive voltage regulator datasheet, buy lmt. Where greater output current is required, the lm350 series regulators are. The nominal output voltage is selected by means of a resistive divider, making the device exceptionally easy to use and eliminating the stocking of many fixed regulators. Lm8lm338 5amp adjustable regulators diyaudioprojects. Thisis nottrue ofother types of positive regulators. An optional output capacitor can be added to improve transient response. Voltage regulator margining using pwm for dynamic voltage scaling. Lm317 vs lm338 page 1 eevblog electronics community forum.
Gate driver voltage bias adjustment using a voltage regulator to drive ganhemt devices. Careful circuit design has resulted in outstanding load and line regulation comparable. The lm317 is an adjustable threeterminal positivevoltage regulator capable of supplying more than 1. Lm338 datasheet, lm338 pdf, lm338 data sheet, lm338 manual, lm338 pdf. Description the lm8, lm238, lm338 are adjustable 3terminal positive voltage regulators, regulated as long as the maximum input to input differential is not exceeded. The dischargecurrent depends on the valueof thecapacitor, the output voltage of the regulator, and therate of decrease of vi. The adjustment terminal of the regulator can be bypassed to achieve very high ripple.
It is exceptionally easy to use and requires only two external resistors. It has many application circuits in its datasheet, but this ic is known for being used as a variable voltage regulator. Lm338 pdf, lm338 description, lm338 datasheets, lm338 view. In the lm338 this discharge path is through alarge junction that isable tosustain25a surgewithno problem.