Test scenarios and usage steps of Pusasi Instrument PL series equipment

The PL series of narrow pulse current sources from Pursis Instruments can be used in VCSEL and other test scenarios that require narrow pulse excitation.

PL series devices have two channels:

①. Constant current pulse excitation source, and can simultaneously measure the voltage at both ends of the device under test;

②. Pulse current measurement channel, especially suitable for measuring pulse optical power using external PD;

PL series equipment can output the following waveforms: the amplitude, step value, and number of pulses of the waveform can all be programmable.

①. DC constant current;

②. DC scanning current;

③. Pulse DC current;

④. Pulse scanning current;

The block diagram of LIV testing using the PL series equipment of Pusis Instruments is as follows: It mainly consists of PL series equipment, special connecting lines, test boards, integrating spheres, lasers to be tested, and light receiving PDs. VCSEL lasers generally have a large output optical power, while the received power of PD is small. An integrator is required to attenuate the optical power. At the same time, the reflection characteristics of the integrating sphere make the laser system not very sensitive to the incident angle of the laser light.

The equipment output has the following signals: LD+, LD-, S+, S-, PD+, PD-, where LD+ and LD- are the constant current source output excitation signals, S+ and S- are the voltage measurement signals of the device under test, PD+, PD- is the external PD measurement signal.

In order to ensure the signal output quality, PL series equipment needs to use special connection lines customized by Pusasi. At the same time, the connections from the test board to the device under test should be minimized. It is best to solder the device directly to the test board or use a socket.

In order to ensure the accuracy of the voltage measurement of the device under test, S+ and S- need to be short-circuited to LD+ and LD- on the pins of the device under test. Please be sure to connect S+ and S- to the pins of the device under test. Do not directly Feel free to short circuit on the test board.