- Operation from 1V to 40V
- 0.02%/V current regulation
- Programmable from 1μA to 10mA
- True 2-end operation
- Available as a fully specified temperature sensor
- Initial accuracy of ± 3%
illustrate
The LM134/LM234/LM334 are characterized by 3-terminal adjustable operating current, excellent current regulation and a wide dynamic voltage range of 10000:1 current source from 1V to 40V. An external resistor is currently built and nowhere else is required. The initial current accuracy is ± 3%. The LM134/LM234/LM334 are true floating, no separate power supply connected current sources. In addition, using reverse voltages up to 20V will result in only a few tens of microamps, thus acting as both a rectifier and a current source in AC applications.
The sense voltage used to settle the current operating at the LM134 at 25°C at 64mV is proportional to absolute temperature (°K). The simplest one is to connect an external resistor, and then, generate a temperature-dependent current with [approximate] +0.33%/°C. Zero drift operation can be achieved by adding an additional resistor and diode.
Applications for current sources include bias networks, surge protection, low-power references, apron generation, LED drivers, and temperature sensing. The LM234-3 and LM234-6 are designated as true temperature sensors with guaranteed ± 3°C and ±6°C, respectively, initial accuracy. These devices are ideal for remote sensing applications because of the range of long wire resistances that operate without compromising accuracy. In addition, only 2 lines are required.
The LM134 is guaranteed to have a temperature range of 125°C at -55°C, the LM234 from -25°C to +100°C and the LM334 from 0°C to +70°C These devices are available in TO-46 sealed TO-92 and SO-8 plastic packages.
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