LSM 350 Current Source


Meet the requirements for production testing of LEDs and LED wafers easily. The LSM 350 source and measure unit was specifically developed to allow all important parameters of LEDs to be determined quickly and reliably.

Because the LSM 350 allows for short settling times you can get up to 40% shorter test cycles in comparison to most standard current sources. Polarity identification and reversal are automatic, ensuring that current is supplied to the LED with correct polarity, irrespective of single or multi-chip LED. Dedicated measurement ranges yield precise testing at low forward currents of 1 µA, and measurement of reverse currents in the nA range. Every test channel is designed for 4-wire measurements. Additional options facilitate measurement of breakdown voltage up to 40 V.

The LSM 350 shows is particularly strong when several channels are used for measuring multichip LEDs. Electrical measurements are precisely timed on all dies, shortening the duration of the test cycle compared with other current sources:

Four channels LSM 350 Rival model
1x optical test at 10 mA 36 ms 67 ms
1x electrical test 35 ms 60 ms
Standard job 218 ms 282 ms

LSM 350 is optimized for the use with precise array spectrometers CAS 140CT or CAS 120 from Instrument Systems. As an LED Tester, this proven turnkey system for LED production testing, can be fitted with an array spectrometer and a LSM-350 current source with up to 4 test channels.

PDF Click here for the LSM 350 Brochure.


  • Very short test cycles and parallel electrical measurements
  • 0 – 350 mA; 0 – 8 V
  • Up to 4 test channels with optional switch matrix
  • Dedicated test channel for μA range
  • Measurement of breakdown voltage up to 40 V
  • The current and voltage source is based on a modular concept. The basic 1-channel unit already integrates all the necessary characteristics in a chassis model.