1FEATURES

2• 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

DESCRIPTION

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.