TYPICAL USAGE AND WAVEFORMS
The AVR-D3-B generates high-voltage, high-current waveforms that are suitable for a
number of transistor turn-on time, turn-off time, and storage time tests.
The setup shown below is appropriate for testing the 2N5686 NPN transistor, based on
the MIL-PRF-19500/464G specification. (Note that Figure 2 of MIL-PRF-19500/464G
apparently has an error where it specifies VBB = 4.0V. It should actually be negative,
i.e., -4.0V).
TURN-ON TEST
Table 1 of MIL-PRF-19500/464G specifies that the turn-on tests should be performed
with a forward base current of +2.5A. This corresponds to a V1 setting for V
PULSE
of:
V1 ≈ (R
OUT
+ 4Ω) × 2.5A + 0.7V = +135.7V
Under these conditions, the voltage at V
IN
will be approximately:
V
IN
≈ (4Ω × 2.5A) + 0.7V = +10.7V
Before the turn-on state, the input to the biased-off transistor is specified to be -2V in
Figure 2 of MIL-PRF-19500/464G. Thus we set V2 = -2V on the AVR-D3-B. Since no
current flows in the reverse state in this test, there is no voltage drop.
With the PRF set to 10 Hz, PW1 set to 10 us, PW2 set to 30 us, and a 10 us delay
setting, the following waveforms are obtained for V
IN
and V
OUT
(as defined in the
diagram above):
V
PULSE
R
OUT
= 50Ω
User's
coaxial
cabling
Typical user-supplied
test circuit
AVR-D3-B-MS1
OUT
MON
R
MON
= 50Ω
V
OUT
, to
oscilloscope
VCC = +30V
1.25Ω
4Ω
VBB = -4V
1N914
2N5686
V
MON
, to
oscilloscope
V
IN
, to
oscilloscope
V
CURR-MON
, to
oscilloscope
25
Summary of Contents for AVR-D3-B
Page 36: ...PCB 158R5 LOW VOLTAGE POWER SUPPLY ...
Page 37: ...PCB 168C HIGH VOLTAGE POWER SUPPLY ...
Page 38: ...PCB 228C NEGATIVE UV CONTROL PCB ...
Page 39: ...PCB 241C DUAL PW PCB ...
Page 40: ...PCB 335A DUAL TRIGGER ENCODER ...
Page 41: ...PCB 104G KEYPAD DISPLAY BOARD ...
Page 43: ...PERFORMANCE CHECK SHEET ...