Avtech AVR-EB2A-B, Instructions Manual

Page: 25 / 71

BASIC AMPLITUDE CONTROL
The basic test arrangement for the AVR-EB2A-B is shown in the figure below. The OUT
output on the instrument mainframe is connected to the IN input on the test jig (model
AVX-CA-AXPOST, or a customized variant) using the supplied coaxial cable, and the
control cable is connected using the supplied DB-9 cable.
The OUT output on the test jig must be connected (using the supplied 60 cm SMA-to-
SMA cable and 20 dB attenuator) to the 50 Ohm input of a high-bandwidth (> 1 GHz)
user-supplied oscilloscope. The voltage on the output is proportional to the current
through the DUT. By observing the current waveform through the DUT, the reverse
recovery time may be determined. When connected as shown above, the oscilloscope
voltage waveform is related to the device current by:
VSCOPE = IDUT × 50Ω / 10
25
AVTECH
AVR-EB2A-B
MAINFRAME
OUT
SYNC
CONTROL
AVX-CA TEST JIG
EXT TRIG
V
PULSE
,
-24V MAXIMUM
0V
VOLTAGE PULSE
CURRENT THROUGH DUT (I
DUT
)
CONTROL
IN
I
R
, -100 mA MAX.
0 mA
I
F
, +100 mA MAX.
REVERSE
RECOVERY
TIME (t
RR
)
DUT
I
DUT
2 meter
DB-9
CABLE
V
PULSE
, up
to -24V
Up to
+115V
V
DC
Other signals ...
Other signals ...
R
DC
= 950Ω
V
SCOPE
= I
DUT
× 50Ω / 10
OSCILLOSCOPE
(BW > 1 GHz)
CH A
R
SCOPE
= 50Ω
20 dB
ATTENUATOR
(USE SUPPLIED
SMA-BNC
ADAPTER, IF
REQUIRED)
R
PULSE
= 50Ω
V
OUT
= I
DUT
× 50Ω
200 ns
I
F
≈ (V
DC
– V
DIODE
) / 1 kΩ
I
R
≈ I
F
+ V
PULSE
/ 100 Ω
60 cm
SMA-to-SMA
COAXIAL
CABLE
OUT
60 cm
SMA-to-SMA
COAXIAL
CABLE