PiezoDrive TD250 V8, Руководство и спецификации

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TD250 V8 Manual 13 Rev 2, 31-09-2020
13.4 Noise Test Conditions
The output noise of the TD250 was measured with the standard DSUB cables and breakout boxes (as
supplied). All inputs on the input breakout box were directly connected to signal ground using the
screw terminal connector. A test capacitor was connected between the output of interest and ground
using the screw terminals on the breakout box. The output voltage was directly connected to a
SRS560 low-noise amplifier with a gain of 1000 and bandwidth of 0.03 Hz to 1 MHz. This signal is of
sufficient amplitude that it can be recorded with an oscilloscope and spectrum analyser.
14 Overload Protection
The overload protections mechanisms are listed below:
Overload Behaviour
Indicator
Peak current
Short circuit If the peak current limit is exceeded for any reason,
the output current is limited to 14 mA DC. None – distorted
waveform
Average current
If the RMS output current is exceeded for more than
10 ms, the output current will be limited to 14 mA
DC or 28mA RMS.
None – distorted
waveform
Total current
The internal high-voltage supply is limited to a total
current limit of 60 mA average and 300 mA peak. If
this is exceeded, the supply voltage will be reduced. Status signal drops below
1V and front panel LED
glows red
Temperature
If the heatsink temperature exceeds 70 C, the high-
voltage supply will be disabled until the
temperature reduces. Status signal drops below
1V and front panel LED
glows red
Table 4. Overload conditions and behaviour
14.1 Status Signal
The Status signal on the front panel connector is nominally 5V during normal operation. The Status
signal drops below 1V when either of the HV supplies drop below 240V due to a fault condition. The
output impedance of this signal is 100 kOhm, it should be measured with a high impedance.
If the Status signal is pulled low due to a fault condition or disable command, the front panel LED
glows red. During startup, the LED will glow red for approximately 1 s.
14.2 Disable Command
Applying a positive voltage of between 3V and 5V to the disable pin on the front panel connector will
turn off the amplifier. The input impedance is approximately 2 kOhm. The absolute maximum input
voltage is +/-10V.