The LM134/LM234/LM334 are 3-terminal adjustable current sources characterized by a operating current range of 10000:1, an excellent current regulation and a wide dynamic voltage range of 1V to 10V. The current is determined by an external resistor without requiring other external components. Reverse voltages of up to 20V will only draw a current of several microamperes. This enables the circuit to operate as a rectifier and as a source of current in a.c. applications. For the LM134/LM234/LM334, the voltage on the control pin is 64mV at +25°C and is directly proportional to the absolute temperature (°K). The simplest external resistor connection generates a current with ≈ 0.33%/°C temperature dependence. Zero drift can be obtained by adding an additional resistor and a diode to the external circuit.
The LM134, LM234, and LM334 are three‑terminal adjustable current sources that operate from 1 V to 40 V and offer 0.02 %/V current regulation. The output current is set by a single external resistor, eliminating the need for additional components. These devices can also function as rectifiers in AC applications, handling reverse voltages up to 20 V with only microampere leakage.
The datasheet includes absolute maximum ratings, detailed electrical characteristics, typical application circuits, and mechanical dimensions for TO‑92 and bulk packages. It also provides guidance on slew rate, thermal effects, shunt capacitance, and noise performance, helping designers implement precise current sources and temperature sensors.
| Forward Voltage (LM134) | 40 V |
|---|---|
| Reverse Voltage (LM134/LM234/LM334) | 20 V |
| Maximum Power Dissipation | 400 mW |
| Storage Temperature Range | -65 °C to +150 °C |
| Operating Temperature Range (LM134) | -55 °C to +125 °C |
| Effective Shunt Capacitance | 15 pF |
The voltage on the control pin is 64 mV at +25 °C.
The typical shunt capacitance is 15 pF.
They are available in TO‑92, TO‑92 tape & reel, and bulk TO‑92 packages.