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LM234

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100°C 3-pin adjustable current source

Product details

Iout/Iz (max) (mA) 0.01 Vin (min) (V) 0.8 Vin (max) (V) 40 Operating temperature range (°C) -25 to 100 Initial accuracy (max) (%) 3 Rating Catalog
Iout/Iz (max) (mA) 0.01 Vin (min) (V) 0.8 Vin (max) (V) 40 Operating temperature range (°C) -25 to 100 Initial accuracy (max) (%) 3 Rating Catalog
TO-92 (LP) 3 19.136 mm² 5.2 x 3.68
  • Operates From 1V to 40V
  • 0.02%/V Current Regulation
  • Programmable From 1µA to 10mA
  • True 2-Terminal Operation
  • Available as Fully Specified Temperature Sensor
  • ±3% Initial Accuracy

All trademarks are the property of their respective owners.

  • Operates From 1V to 40V
  • 0.02%/V Current Regulation
  • Programmable From 1µA to 10mA
  • True 2-Terminal Operation
  • Available as Fully Specified Temperature Sensor
  • ±3% Initial Accuracy

All trademarks are the property of their respective owners.

The LM134/LM234/LM334 are 3-terminal adjustable current sources featuring 10,000:1 range in operating current, excellent current regulation and a wide dynamic voltage range of 1V to 40V. Current is established with one external resistor and no other parts are required. Initial current accuracy is ±3%. The LM134/LM234/LM334 are true floating current sources with no separate power supply connections. In addition, reverse applied voltages of up to 20V will draw only a few dozen microamperes of current, allowing the devices to act as both a rectifier and current source in AC applications.

The sense voltage used to establish operating current in the LM134 is 64mV at 25°C and is directly proportional to absolute temperature (°K). The simplest one external resistor connection, then, generates a current with ≈+0.33%/°C temperature dependence. Zero drift operation can be obtained by adding one extra resistor and a diode.

Applications for the current sources include bias networks, surge protection, low power reference, ramp generation, LED driver, and temperature sensing. The LM234-3 and LM234-6 are specified as true temperature sensors with ensured initial accuracy of ±3°C and ±6°C, respectively. These devices are ideal in remote sense applications because series resistance in long wire runs does not affect accuracy. In addition, only 2 wires are required.

The LM134 is specified over a temperature range of −55°C to +125°C, the LM234 from −25°C to +100°C and the LM334 from 0°C to +70°C. These devices are available in TO hermetic, TO-92 and SOIC-8 plastic packages.

The LM134/LM234/LM334 are 3-terminal adjustable current sources featuring 10,000:1 range in operating current, excellent current regulation and a wide dynamic voltage range of 1V to 40V. Current is established with one external resistor and no other parts are required. Initial current accuracy is ±3%. The LM134/LM234/LM334 are true floating current sources with no separate power supply connections. In addition, reverse applied voltages of up to 20V will draw only a few dozen microamperes of current, allowing the devices to act as both a rectifier and current source in AC applications.

The sense voltage used to establish operating current in the LM134 is 64mV at 25°C and is directly proportional to absolute temperature (°K). The simplest one external resistor connection, then, generates a current with ≈+0.33%/°C temperature dependence. Zero drift operation can be obtained by adding one extra resistor and a diode.

Applications for the current sources include bias networks, surge protection, low power reference, ramp generation, LED driver, and temperature sensing. The LM234-3 and LM234-6 are specified as true temperature sensors with ensured initial accuracy of ±3°C and ±6°C, respectively. These devices are ideal in remote sense applications because series resistance in long wire runs does not affect accuracy. In addition, only 2 wires are required.

The LM134 is specified over a temperature range of −55°C to +125°C, the LM234 from −25°C to +100°C and the LM334 from 0°C to +70°C. These devices are available in TO hermetic, TO-92 and SOIC-8 plastic packages.

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Type Title Date
* Data sheet LM134/LM234/LM334 3-Terminal Adjustable Current Sources datasheet (Rev. E) 20 Jun 2013
E-book Tips and tricks for designing with voltage references (Rev. A) 07 May 2021
Application note Precision Current Sources and Sinks Using Voltage References 30 Jun 2020
E-book Voltage Supervisor and Reset ICs: Tips, Tricks and Basics 28 Jun 2019
Application note TO-92 Packing Options / Ordering Instructions (Rev. A) 23 Jun 2010

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Shunt voltage references
ATL431 2.5-V low-IQ adjustable precision shunt regulator LM136-2.5-N Voltage Reference Diode LM136-5.0 5.0V Reference Diode LM136-5.0QML 5.0V Reference Diode LM136A-2.5QML 2.5V Reference Diode LM136A-2.5QML-SP Radiation-hardened QMLV, 2.5-V shunt voltage reference LM136A-5.0QML 5.0V Reference Diode LM185-1.2-N Micropower Voltage Reference Diode LM185-1.2QML Micropower Voltage Reference Diode LM185-1.2QML-SP Radiation-hardened QMLV, 1.2-V shunt voltage reference LM185-2.5-N Micropower Voltage Reference Diode LM185-2.5QML Micropower Voltage Reference Diode LM185-2.5QML-SP Space-grade QMLV 2.5-V  shunt voltage reference LM185-ADJ Adjustable Micropower Voltage Reference LM185QML Adjustable Micropower Voltage Reference LM285-1.2 1.235-V, –40°C to +85°C, micropower voltage reference LM285-1.2-N 1.235-V, –40°C to +85°C, micropower voltage reference diode LM285-2.5 2.5-V, –40°C to +85°C, micropower voltage reference LM285-2.5-N 2.5-V, –40°C to +85°C, micropower voltage reference diode LM285-ADJ Adjustable, 85°C, micropower voltage reference LM336-2.5 0°C to 70°C, 2.5-V integrated reference circuit LM336-2.5-N Voltage reference diode LM336-5.0 5-V reference diode LM385-1.2 1.235-V, 2%, 0°C to 70°C, micropower voltage reference LM385-1.2-MIL Micropower Voltage Reference LM385-1.2-N 1.235-V, 0°C to 70°C, micropower voltage reference diode LM385-2.5 2.5-V, 2%, 70°C, micropower voltage reference LM385-2.5-N 2.5-V, 0°C to 70°C, micropower voltage reference diode LM385-ADJ Adjustable, 70°C, micropower voltage reference LM4030 Ultra-high-precision shunt voltage reference LM4040 Fixed voltage, 45-µA, precision micropower shunt voltage reference LM4040-N 100-ppm/°C precision micropower shunt voltage reference LM4040-N-Q1 Automotive, 100-ppm/°C precision micropower shunt voltage reference LM4041-N Fixed & adjustable, 45-µA, precision micropower shunt voltage reference LM4041-N-Q1 Automotive, precision micropower shunt voltage reference LM4050-N 50-ppm/°C precision micropower shunt voltage reference LM4050-N-Q1 Automotive, 50-ppm/°C precision micropower shunt voltage reference LM4050QML-SP Radiation-hardened QMLV, 2.5-V or 5-V shunt voltage reference LM4051-N Fixed & adjustable, precision micropower shunt voltage reference LM431 2%, 1%, or 0.5% accuracy, adjustable precision Zener shunt regulator LM4431 Micropower shunt voltage reference LMV431 1.5%, low-voltage (1.24-V) adjustable precision shunt regulator LMV431A 1%, low-voltage (1.24-V) adjustable precision shunt regulator LMV431B 0.5%, low-voltage (1.24-V) adjustable precision shunt regulator
Current references
LM134 3-Terminal Adjustable Current Source LM234 100°C 3-pin adjustable current source LM334 0°C to 70°C 3-pin adjustable current source
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