LM334D STMicroelectronics

LM134-LM234-LM334 Three terminal adjustable current sources Features Operates from 1V to 40V 0.02%/V current regulation Programmable from 1A to 10mA Z TO-92 3% initial accuracy (Plastic package) Description The LM134/LM234/LM334 are 3-terminal adjustable current sources characterized by: an operating current range of 10000: 1 D SO-8 an excellent current regulation (Plastic micropackage) a wide dynamic voltage range of 1V t 10V The current is determined by an external resistor without requiring other external components. Pin connections Reverse voltages of up to 20V will only draw a current of several microamperes. This enables the TO-92 circuit to operate as a rectifier and as a source of (Bottom view) current in a.c. applications. For the LM134/LM234/LM334, the voltage on the v+ ADJ v- 21 3 control pin is 64mV at +25C and is directly proportional to the absolute temperature (K). The simplest external resistor connection generates a current with approximately 0.33%/C temperature dependence. Zero drift can be obtained by adding an additional resistor and a diode to the external circuit. SO-8 (Top view) NC NC V- NC 8765 1234 ADJ NC V+ NC May 2007 Rev 3 1/16 www.st.com 16Schematic diagram LM134-LM234-LM334 1 Schematic diagram Figure 1. Schematic diagram 2 Absolute maximum ratings Table 1. Absolute maximum ratings Symbol Parameter LM134 LM234 LM334 Unit Voltage V+ to V- V Forward 40 30 Reverse 20 20 - - V ADJ pin to V voltage 5 V ADJ I Set current 10 mA set P Power dissipation 400 mW tot T Storage temperature range -65 to +150 C stg T Operating free-air temperature range -55 to +125 -25 to +100 0 to +70 C oper 2/16