Avtech 14258, Инструкция по эксплуатации

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INTRODUCTION
The AVR-EB4-B-NXPB-SOD123W is a high performance, GPIB/RS232/Ethernet-
equipped customized instrument capable of generating a bipolar waveform into a test
jig. Normally, a diode will be placed installed in the jig, allowing diode currents of up to
+0.5A and -1A to be generated. When used with a user-supplied oscilloscope, this
instrument is useful for measuring reverse recovery times (t
RR
) of 8 ns to 1 us.
The AVR-EB4-B-NXPB-SOD123W mainframe generates two pulses internally, which
are combined using a resistor/capacitor network.
A 100 us wide forward-bias pulse of V
1
= +1 to +120V is connected to the mainframe
output through a 175Ω resistance. With a diode DUT (with a forward voltage drop of
V
DIODE
) and another 25Ω total resistance in the connected jig and oscilloscope, the
forward bias current is given by:
I
F
= (V
1
– V
DIODE
) / 200Ω, approximately
+0.5A maximum, approximately
80 us after the forward bias pulse starts, a 2 us wide reverse-bias pulse of V2 = -7.5 to -
84V is capacitively coupled to the mainframe output. This generates a current of:
I
R
= I
F
+ (V
2
/ 50Ω), approximately
-1A maximum, approximately
The forward-to-reverse switching time is < 1.5 ns (10%-90%).
The maximum reverse voltage that will develop across the DUT is:
V
RMAX
= I
R
× 50Ω
The DUT breakdown voltage must exceed this value.
The AVR-EB4-B-NXPB-SOD123W includes one AVX-TRR-NXPB-SOD123W diode test
jig. The instrument mainframe is connected to the test jig using two coaxial cables and
one DB-9 control cable. This jig accepts SOD123W packages.
The test jig output should be terminated with 50 Ohms, and connected to a high-
bandwidth (> 400 MHz) oscilloscope. The voltage across this resistance is directly
proportional to the current through the diode. By observing the current waveform
through the diode, the reverse recovery time may be determined.
While the provided test jig is intended to be flexible and easy to use, users can also
develop their own test jigs easily.
The AVR-EB4-B-NXPB-SOD123W may also be provided with different or additional a
customized test jigs, to meet particular customer package requirements.
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