General Description The LM134/LM234/LM334 are 3-terminal adjustable current sources with a 10000:1 operating current range, excellent current regulation voltage and a wide dynamic range of 1V to 40V. Currently an external resistor is built and nowhere else is required. Initial current accuracy ±3%. It is true that the LM134/LM234/LM334 floating current sources do not have separate power connections. Additionally, applications with reverse voltages up to 20V will draw only a few tens of microamps of current, thus acting as both a rectifier and a current source in AC applications for the device. The detection voltage used to establish the current operating LM134 is 64mV at 25°C and is absolutely proportional to the temperature (°K). The simplest connection of an external resistor, then, generates a temperature dependence of »0.33% current/°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, tarmac generation, LED drivers, and temperature sensing. The LM234-3 and LM234-6 are specified as true temperature sensors with guaranteed initial accuracy of ±3°C and ±6°C respectively. These devices are ideal for remote sensing applications because the series performs long wire resistance without compromising accuracy. Also, only 2 wires are required. The LM134 is guaranteed over a temperature range of -55°C to +125°C, and -25°C to +100°C. The LM234 and LM334 are available from 0°C to +70°C in a TO-46 hermetic TO-92 and SO-8 plastic packages.

Features Operation from 1V to 40V
0.02%/V current regulation programmable from 1µA to 10mA
True 2-terminal operation as a fully specified temperature sensor with an initial accuracy of ±3%