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LM317
The LM317 is a popular adjustable positive linear voltage regulator. It was designed by Bob Dobkin in 1976 while he worked at National Semiconductor. The LM337 is the negative complement to the LM317, which regulates voltages below a reference. It was designed by Bob Pease, who also worked for National Semiconductor. Specifications Without a heat sink with an ambient temperature at 50 °C such as on a hot summer day inside a box, a maximum power dissipation of (TJ-TA)/RθJA = ((125-50)/80) = 0.98 W can be permitted. (A piece of shiny sheet metal of aluminium with the dimensions 6 x 6 cm and 1.5 mm thick, results in a thermal resistance that permits 4.7 W of heat dissipation). In a constant voltage mode with an input voltage source at VIN at 34 V and a desired output voltage of 5 V, the maximum output current will be PMAX / (VI-VO) = 0.98 / (34-5) = 32 mA. For a constant current mode with an input voltage source at VIN at 12 V and a forward voltage drop of VF=3.6 ...
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LM317 1A ConstCurrent
The LM317 is a popular adjustable positive linear voltage regulator. It was designed by Bob Dobkin in 1976 while he worked at National Semiconductor. The LM337 is the negative complement to the LM317, which regulates voltages below a reference. It was designed by Bob Pease, who also worked for National Semiconductor. Specifications Without a heat sink with an ambient temperature at 50 °C such as on a hot summer day inside a box, a maximum power dissipation of (TJ-TA)/RθJA = ((125-50)/80) = 0.98 W can be permitted. (A piece of shiny sheet metal of aluminium with the dimensions 6 x 6 cm and 1.5 mm thick, results in a thermal resistance that permits 4.7 W of heat dissipation). In a constant voltage mode with an input voltage source at VIN at 34 V and a desired output voltage of 5 V, the maximum output current will be PMAX / (VI-VO) = 0.98 / (34-5) = 32 mA. For a constant current mode with an input voltage source at VIN at 12 V and a forward voltage drop of VF=3.6 ...
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LM317 TO-220
The LM317 is a popular adjustable positive linear voltage regulator. It was designed by Bob Dobkin in 1976 while he worked at National Semiconductor. The LM337 is the negative complement to the LM317, which regulates voltages below a reference. It was designed by Bob Pease, who also worked for National Semiconductor. Specifications Without a heat sink with an ambient temperature at 50 °C such as on a hot summer day inside a box, a maximum power dissipation of (TJ-TA)/RθJA = ((125-50)/80) = 0.98 W can be permitted. (A piece of shiny sheet metal of aluminium with the dimensions 6 x 6 cm and 1.5 mm thick, results in a thermal resistance that permits 4.7 W of heat dissipation). In a constant voltage mode with an input voltage source at VIN at 34 V and a desired output voltage of 5 V, the maximum output current will be PMAX / (VI-VO) = 0.98 / (34-5) = 32 mA. For a constant current mode with an input voltage source at VIN at 12 V and a forward voltage drop of VF=3.6 ...
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LM317 Typical Schematic
The LM317 is a popular adjustable positive linear voltage regulator. It was designed by Bob Dobkin in 1976 while he worked at National Semiconductor. The LM337 is the negative complement to the LM317, which regulates voltages below a reference. It was designed by Bob Pease, who also worked for National Semiconductor. Specifications Without a heat sink with an ambient temperature at 50 °C such as on a hot summer day inside a box, a maximum power dissipation of (TJ-TA)/RθJA = ((125-50)/80) = 0.98 W can be permitted. (A piece of shiny sheet metal of aluminium with the dimensions 6 x 6 cm and 1.5 mm thick, results in a thermal resistance that permits 4.7 W of heat dissipation). In a constant voltage mode with an input voltage source at VIN at 34 V and a desired output voltage of 5 V, the maximum output current will be PMAX / (VI-VO) = 0.98 / (34-5) = 32 mA. For a constant current mode with an input voltage source at VIN at 12 V and a forward voltage drop of VF=3.6 ...
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Linear Regulator
In electronics, a linear regulator is a voltage regulator used to maintain a steady voltage. The resistance of the regulator varies in accordance with both the input voltage and the load, resulting in a constant voltage output. The regulating circuit varies its resistance, continuously adjusting a voltage divider network to maintain a constant output voltage and continually dissipating the difference between the input and regulated voltages as waste heat. By contrast, a ''switching regulator'' uses an active device that switches on and off (oscilates) to maintain an average value of output. Because the regulated voltage of a linear regulator must always be lower than input voltage, efficiency is limited and the input voltage must be high enough to always allow the active device to drop some voltage. Linear regulators may place the regulating device in parallel with the load ( shunt regulator) or may place the regulating device between the source and the regulated load (a series re ...
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Bandgap Voltage Reference
A bandgap voltage reference is a temperature independent voltage reference circuit widely used in integrated circuits. It produces a fixed (constant) voltage regardless of power supply variations, temperature changes, or circuit loading from a device. It commonly has an output voltage around 1.25V (close to the theoretical band gap of silicon at absolute zero, 0K). This circuit concept was first published by David Hilbiber in 1964. Bob Widlar, Paul Brokaw and others followed up with other commercially successful versions. Operation The voltage difference between two p–n junctions (e.g. diodes), operated at different current densities, is used to generate a current that is ''proportional to absolute temperature'' (''PTAT'') in a resistor. This current is used to generate a voltage in a second resistor. This voltage in turn is added to the voltage of one of the junctions (or a third one, in some implementations). The voltage across a diode operated at constant current is ...
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Brokaw Bandgap Reference
Brokaw bandgap reference is a voltage reference circuit widely used in integrated circuits, with an output voltage around 1.25 V with low temperature dependence. This particular circuit is one type of a bandgap voltage reference, named after Paul Brokaw, the author of its first publication. Brokaw, P., "A simple three-terminal IC bandgap reference", ''IEEE Journal of Solid-State Circuits'', vol. 9, pp. 388–393, December 1974. Like all temperature-independent bandgap references, the circuit maintains an internal voltage source that has a positive temperature coefficient and another internal voltage source that has a negative temperature coefficient. By summing the two together, the temperature dependence can be canceled. Additionally, either of the two internal sources can be used as a temperature sensor. In the Brokaw bandgap reference, the circuit uses negative feedback (by means of an operational amplifier) to force a constant current through two bipolar transistors wi ...
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List Of LM-series Integrated Circuits
The following is a list of LM-series integrated circuits. Many were among the first analog integrated circuits commercially produced since late 1965; some were groundbreaking innovations. As of 2007, many are still being used. The LM series originated with integrated circuits made by National Semiconductor. The prefix LM stands for ''linear monolithic'', referring to the analog components integrated onto a single piece of silicon. Because of the popularity of these parts, many of them were second-sourced by other manufacturers who kept the sequence number as an aid to identification of compatible parts. Several generations of pin-compatible descendants of the original parts have since become ''de facto'' standard electronic components. Operational amplifiers Differential comparators Current-mode (Norton) amplifiers Instrumentation amplifiers Audio amplifiers Precision reference Voltage regulators Voltage-to-frequency converters Current s ...
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78xx
78xx (sometimes L78xx, LM78xx, MC78xx...) is a family of self-contained fixed linear voltage regulator integrated circuits. The 78xx family is commonly used in electronic circuits requiring a regulated power supply due to their ease-of-use and low cost. Nomenclature and packaging For ICs within the 78xx family, the ''xx'' is replaced with two digits, indicating the output voltage (for example, the 7805 has a 5-volt output, while the 7812 produces 12 volts). The 78xx line are positive voltage regulators: they produce a voltage that is positive relative to a common ground. There is a related line of 79xx devices which are complementary negative voltage regulators. 78xx and 79xx ICs can be used in combination to provide positive and negative supply voltages in the same circuit. 78xx ICs have three terminals and are commonly found in the TO-220 form factor, although they are available in surface-mount, TO-92, and TO-3 packages. These devices support an input voltage anywhere ...
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Bob Dobkin
Robert C. Dobkin (born 1943 in Philadelphia) is an American electrical engineer, co-founder of Linear Technology Corporation, and veteran linear (analog) integrated circuit (IC) designer. Career Dobkin studied Electrical Engineering at MIT, but did not complete a degree. After early employments e.g. at GE Reentry Systems, he joined Philbrick Nexus in Massachusetts working on IC development with Bob Pease. He joined National Semiconductor (NSC) in January 1969. He resigned the position as Director of Advanced Circuit Development at NSC in July 1981 and co-founded Linear Technology with Robert H. Swanson in the same year. Dobkin continued to serve as the company's Chief Technical Officer through its acquisition by Analog Devices in 2016. He has been a Director of Spectra7 Microsystems Inc. since March 20, 2013. Dobkin holds more than 100 patents in the field of analog circuits. Works * LM118, first high speed operational amplifier. * LM199, heated buried-Zener voltage refer ...
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Bob Pease
Robert Allen Pease (August 22, 1940 – June 18, 2011) was an electronics engineer known for analog integrated circuit (IC) design, and as the author of technical books and articles about electronic design. He designed several very successful "best-seller" ICs, many of them in continuous production for multiple decades.These include LM331 voltage-to-frequency converter, and the LM337 adjustable negative voltage regulator (complement to the LM317). Life and career Pease was born on August 22, 1940 in Rockville, Connecticut. He attended Northfield Mount Hermon School in Massachusetts, and subsequently obtained a Bachelor of Science in Electrical Engineering (BSEE) degree from Massachusetts Institute of Technology in 1961. He started work in the early 1960s at George A. Philbrick Researches (GAP-R). GAP-R pioneered the first reasonable-cost, mass-produced operational amplifier (op-amp), the K2-W. At GAP-R, Pease developed many high-performance op-amps, built with discrete so ...
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Halbleiterwerk Frankfurt (Oder)
VEB Halbleiterwerk Frankfurt (Oder) (abbreviated HFO or HWF) was the largest manufacturer of semiconductor devices in the German Democratic Republic. In 1989, HFO produced 110 million integrated circuits (70% of all integrated circuits produced in the GDR in that year), 9.7 million transistors, and 150 million transistor chips. Despite this, HFO did not rise to prominence like Zentrum Mikroelektronik Dresden (of '' megabit chip'' fame) or VEB Mikroelektronik "Karl Marx" Erfurt (known for its microprocessors). Also unlike Zentrum Mikroelektronik Dresden and VEB Mikroelektronik "Karl Marx" Erfurt, HFO did not survive long after German Reunification. History In January 1958, the production of Germanium diodes started in the building of a former vocational school. Halbleiterwerk Frankfurt (Oder) was officially founded on 1 January 1959. In January 1961 new production facilities for germanium alloy-junction transistors and diodes went into operation in the Markendorf quarter of Fran ...
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79xx
78xx (sometimes L78xx, LM78xx, MC78xx...) is a family of self-contained fixed linear voltage regulator integrated circuits. The 78xx family is commonly used in electronic circuits requiring a regulated power supply due to their ease-of-use and low cost. Nomenclature and packaging For ICs within the 78xx family, the ''xx'' is replaced with two digits, indicating the output voltage (for example, the 7805 has a 5-volt output, while the 7812 produces 12 volts). The 78xx line are positive voltage regulators: they produce a voltage that is positive relative to a common ground. There is a related line of 79xx devices which are complementary negative voltage regulators. 78xx and 79xx ICs can be used in combination to provide positive and negative supply voltages in the same circuit. 78xx ICs have three terminals and are commonly found in the TO-220 form factor, although they are available in surface-mount, TO-92, and TO-3 packages. These devices support an input voltage anywhere f ...
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