PDu100B Miniature Piezo Driver
|Power Supply||3 V to 5.5 V|
|Max. Unipolar Output||+60V||+90 V||+100 V|
|Max. Bipolar Output||+/-60 V||+/-90 V||+/- 100 V|
|Av. Output Current||+/-40 mA||+/-18mA||+/-15mA|
|Power Bandwidth||5.3 kHz||3.5 kHz||3.2 kHz|
|Peak Output Current||100 mA|
|Signal Bandwidth||60 kHz (unloaded)|
|Dimensions||39 x 25 mm (1.5 x 1 in)|
|Weight||5.5 g (0.2 oz)|
|Input Impedance||100 kohm 20 kohm|
|Input Offset||+/- 100 mV|
|Load||Unlimited capacitance loads|
|Overload||Thermal and current overload protection|
|Noise||70 mV RMS (10uF Load)|
|Environment||-40 to 70 Celsius (-40 to 158 F)
|Input Offset||25 mA (1 mA in Shutdown)|
- The PDu100B is a complete miniaturized power supply and linear amplifier for driving piezoelectric actuators. The PDu100B provides variable gain and offset, switchable voltage ranges, and the choice between ground referenced or differential inputs and outputs. The PDu100B can drive two-wire piezoelectric actuators and benders up to +/-100V and three-wire piezoelectric benders and stack actuators up to +100V. Applications include piezoelectric valves, motors, pumps and low-power positioning and manipulation systems.
- Key features include:
- Selectable output voltage range 100V, 90V, or 60V
- Bipolar or unipolar output
- Bias supply for three-wire bender actuators
- Peak output current: 100mA
- Average output current: 40mA
- Supply voltage: 3V to 5.5V
- Dimensions: 25x40mm (1x1.5in)
- Mass: 5.5 grams (0.2oz)
The PDu100B can be configured to suit a wide variety of applications. The output voltage range is selected by Switch 1 (S1) as shown below.
|S1.1||S1.2||Unipolar Range||Bipolar Range|
|On||On||100 V||+/-100 V|
|On||Off||90 V||+/-90 V|
|Off||On||70 V||+/-70 V|
|Off||Off||60 V||+/-60 V|
The input type can be configured to either unipolar or bipolar with Switch 2 (S2), as shown below.
|Input Type||S2.1||S2.2||Apply to||Input Range|
|Unipolar||On||Off||Vup||0.5Vs +/-1.8 V|
The overall system gain is determined by the configuration of the input and output. The possible combinations are listed below.
|Input Type||Output Type||Gain||Input Range||Output Range|
|Unipolar||Bipolar||55||0.5Vs +/-1.8V||+/-100 V|
Both outputs are biased at approximately half the HV bus voltage VHV, e.g. 50 V with a 100 V range. The output voltage equations are listed below.
|Input Type||Output Type||Output Equation|
The maximum RMS and average DC output current for each voltage range is listed below. The average DC current is the average current flowing in either the positive or negative direction. For a sine wave, the average DC current is related to the RMS current by
|Voltage Range||RMS Current||Average Current|
|60 V||89 mA||40 mA|
|70 V||67 mA||30 mA|
|90 V||60 mA||18 mA|
|100 V||33 mA||15 mA|
For periods less than 100 us, output currents of approximately 100 mA are possible. This is useful for achieving small, high-speed step changes in the output voltage.
UNLOADED POWER BANDWIDTH: The output slew-rate of the PDu100B is 1 V/us. Therefore, the maximum frequency sine-wave is:
The UNLOADED power bandwidth for each voltage range is listed below:
|Voltage Range||Unloaded Power Bandwidth|
|60 V||5.3 kHz|
|70 V||4.5 kHz|
|90 V||3.5 kHz|
|100 V||3.2 kHz|
POWER BANDWIDTH WITH A CAPACITIVE LOAD: With a capacitive load connected, the power bandwidth is limited by the maximum output current.
For a sine wave, the power bandwidth for a UNIPOLAR CAPACITIVE LOAD is listed below.
For a BIPOLAR CAPACITIVE LOAD, the power bandwidth is halved since the voltage range is doubled.
In the following figures, the maximum peak-to-peakvoltage is plotted against frequency for a range of capacitive loads.
Enable / Shutdown
The Enable pin can be pulled low to disable the amplifier and reduce the quiescent current to 1 mA. It can be driven by a logic output or an open collector output. The recovery time after a shut-down is 2 ms.
The PDu100B is protected against over-current and thermal overload. If the temperature exceeds 150 degrees C, the amplifier will be disabled until the temperature reduces.
The lateral dimensions are shown in the first figure. The mounting holes are designed for an M2.5 threaded spacer. The left elevation of the standard and PCB mounting version (PDu100B-PCB) are shown in the second figure.