LM134H

The LM134H is a three-terminal adjustable current source manufactured by Texas Instruments, housed in a hermetically sealed TO-46 metal can package. This device delivers a true current output without the need for external power supply bypassing in many configurations, with an operating voltage range spanning from 1 V to 40 V and a current adjustability typically extending from 1 µA to 10 mA when configured with a single external resistor. Its inherent design provides a dynamic impedance exceeding 10 MΩ and excellent temperature stability, complemented by the TO-46 package’s low thermal resistance and hermetic sealing, which ensures reliable performance in environments demanding resistance to moisture, thermal shock, and mechanical stress.

Typical applications span industrial instrumentation, precision sensor bias for strain gauges and thermocouples, ramp generators, and timing circuits where a stable, programmable current directly enhances analog front-end accuracy. In aerospace and defense systems, the LM134H is employed in radiation-tolerant power management, satellite telemetry biasing, and ruggedized data acquisition modules. Procurement engineers assessing this part for long-lifecycle programs note that the metal can construction aligns with high-reliability and military-grade requirements; similar LM134 variants exist with /883 suffix or source-control drawings to satisfy MIL-STD-883 screening. Ensuring proper traceability and verifying the manufacturer’s ongoing support status are essential steps, as metal can packages gradually transition to limited availability, making lifecycle planning and alternate source evaluation critical for sustainment-focused designs.