Micromechatronics, Inc. (MMech)

www.mmech.com - Ph: 814-861-5688

PDu100 Micro Piezo Driver

Piezoelectric Drivers

Piezodrive_PDu100_medium

pdf-icon_sm PDu100 Specifications

keypad_sm Calculate Power Bandwidth

Specifications:

PDu100 Specifications
Power Supply 3 V to 5.5 V
Max. Unipolar Output +100V
Max. Bipolar Output +/-100 V
RMS Output Current 33 mA
Average DC Current 15 mA
Power Bandwidth 3.2 kHz
Peak Output Current 100 mA
Signal Bandwidth 60 kHz (unloaded)
Dimensions 11.8 x 12.9 mm (0.46 x 0.51 in)
Weight 560 mg (0.018 oz)
Gain 27.5 V/V
Input Voltage Vs/2 +/- 1.8V (Zin = 100k)
Input Offset +/- 100 mV
Load Capacitance Unlimited
Overload Protection Thermal and current
Noise 70 mV RMS (10uF Load)
Environment -40 to 70 Celsius (-40 to 158 F)
Non-condensing humidity
Quiescent Current 25 mA (1 mA in Shutdown)

Features

  • The PDu100 is the industry‚Äôs smallest and lightest driver for piezoelectric actuators. It can be used to drive two-wire piezoelectric actuators and benders up to +/-100 V. It can also drive three-wire piezoelectric benders and stack actuators up to +100 V. Applications include battery powered robotics, piezoelectric motors, and ultra low-power positioning and manipulation systems.
  • Key features include:
    • +/-100V Output voltage range for piezo actuators and two-wire benders
    • +100V Output voltage range for stack actuators
    • Bias supply for three-wire bender actuators
    • Output current: 15mA
    • Supply voltage: 3V to 5.5V
    • Dimensions: 12x13mm (0.5x0.5in)
    • Mass: 0.5 grams (0.018oz)

Connection Diagram

pdu100-connection-336w

Operation

The system block diagram is illustrated in Figure 2. A boost converter generates a high-voltage rail to supply a pair of complementary amplifiers. A single output can be used to drive a unipolar load up to +100 V or both amplifiers can be used to produce +/-100 V.

The input is selectable between a unipolar signal biased at half the supply voltage or a bipolar signal. The amplifier gain is 27.5 so a 3.6 Vp-p input will produce a 100 Vp-p output. Both amplifier channels are biased at half the output range (50 V).

pdu100-operation-339w

The overall system gain is determined by the output configuration. The possible combinations are listed below.

Output Type Gain Input Range Output Range
Unipolar 27.5 0.5 Vs +/- 1.8V 100V
Bipolar 55 0.5 Vs +/- 1.8V +/- 100V
System Gain and Voltage Range

Both outputs are biased at approximately half the HV bus voltage, e.g. 50 V. The output voltage equations are listed below.

Output Type Output Equation
Unipolar Formula1
Bipolar Formula2
System Gain and Voltage Range

Example Applications

pdu100-examples

Output Current

The maximum average output current is 15 mA. However, for periods less than 100 us an output current of approximately 100 mA is possible. This is useful for achieving small, high-speed step changes in the output voltage.

Power Bandwidth

The output slew-rate of the PDu100 is 1 V/us. Therefore, the maximum frequency sine-wave is

PDu100_Unloaded_fmax

The 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

 With a capacitive load, the power bandwidth is limited by the maximum output current. For a sine wave

PDu100_Loaded_fmax

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

Formula_DC

The power bandwidth for a range of load capacitances and output voltages is listed below.

Load (uF) 60 V 100 V +/-100 V
0.01 5300 3200 2300
0.03 2600 1500 790
0.1 790 470 230
0.3 260 150 79
1 79 47 23
3 26 15 8.0
10 8.0 4.8 2.4
30 2.7 1.6 0.8
Power bandwidth versus voltage range and capacitance (in Hz)

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.

PDu100B_100V_Bandwidth

More Information

200 Innovation Blvd. Suite 155
State College, PA 16803, USA
Ph: (814)-861-5688
Fax: (814)-861-1418
contact@mmech.com
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