Always make sure the LED HV ON indicator is OFF before connecting or disconnecting a load on the high voltage connector. Capacitive loads (including piezo elements) may stay charged even when the amplifier output is OFF. Make sure they are discharged before manipulating them.
Connections
Supply / Interlock terminal block connector
- V+ / V-: Input power supply from 19 V to 33 V, nom. 24 V. We recommend using a 24 V / 1.5 A isolated power supply.
- EN+ / EN-: Enable / Disable control input (see Enable / Disable input). If unused, leave unconnected and use the enable switch instead.
High voltage output terminal block connector
- HV OUT: High voltage output
- GND: Ground
SMA connector
The input signal must be connected on the SMA connector (input impedance 1 kΩ). The high voltage output is the input voltage amplified by a factor 20 V/V.
Grounding
The high voltage negative terminal, the input signal SMA connector and the base/top-plates are all connected to GND.
The V- supply return pin is connected to GND via a common-mode filtering choke.
A threaded hole on the baseplate can be used for protective earth mounting using a secured screw (see mechanical drawing).
Operation
- Connect the load to the high voltage terminal output.
- Connect the input signal (up to 10Vpp) to the SMA.
- Adjust the internal power supply (see Adjusting the internal power supply Vcc).
- Connect the supply voltage to V+ / V-.
- Set the enable pin (Configuration switch pin 1) to ON, or apply control signal to EN +/-.
When the high voltage output is enabled the red LED is ON.
⚠ Always make sure the LED is OFF before connecting or disconnecting a load on the high voltage connector.
⚠ Capacitive loads (including piezo elements) may stay charged even when the amplifier output is OFF. Make sure they are discharged before manipulating them.
Configuration switch
SW1: When set to ON, the high-voltage output is enabled. When set to OFF the output enable is controled by the EN+ / EN- input.
SW2: When set to ON, the amplifier has lower noise and higher bandwidth, at the expense of an increased quiescent current.
SW3, SW4, SW5, SW6: Set the output voltage range (see Adjusting the internal power supply Vcc).
Adjusting the internal power supply Vcc
The amplifier is supplied by an internal bipolar power supply that can be adjusted between Vcc = ±45 V and Vcc = ±105 V. Given a desired output voltage range ±Vmax, Vcc must be set to the lowest possible voltage so that Vcc > Vmax + 2 V.
Vcc is set by steps of 4 V with the configuration switches SW3, SW4, SW5 and SW6:
where SWX = 0 when OFF, SWX = 1 when ON.
For example, if the application requires an output range between -50 V and +60 V, Vcc must thus be set to the lowest possible value above Vmax + 2 V = 62 V, which is 45 + 16 + 4 = 65 V. (SW3 = 0 / SW4 = 1 / SW5 = 0 / SW6 = 1).
Enable / Disable input
When the EN configuration switch (SW1) is set to OFF, the output must be enabled via the opto-isolated EN+/EN- pins. The input is compatible with 3.3V or 5V TTL logic. It draws 2.5 mA at 3.3 V and 4 mA at 5 V. Maximum allowed input current is 7 mA and maximum input voltage is 9 V. If a higher input voltage is required, a resistor must be added in series to maintain input current below 7 mA (1 mA is enough to enable the input).
