ORIC
®
Piezo Stage Controller PDXC
Chapter 3: Overview
Rev B, September 23, 2021
Page 3
Chapter 3
Overview
3.1. Introduction
The PDXC Piezo Stage Controller is designed to control our PD1(/M) Piezo Inertia Linear Translation Stage,
PDX1(/M) Piezo Inertia Linear Translation Stage with an Optical Encoder, and PDR1(/M) Piezo Inertia Rotation
Stage. It offers two channels of open-loop stage control (SMC outputs), and one channel of both open- and closed-
loop stage control (15-Pin D-SUB output). The user can easily switch between operations by turning the knob after
powering on the unit. It also supports remote PC control via the USB or RS-232 ports on the back panel, and a USB
mouse can be connected to the front panel for intuitive control. The product supports daisy-chain mode in which
several controllers work together to move multiple stages at very low delay by inserting RJ-45 cables between them.
The controller also supports external I/O control, including analog in and out, and trigger in and out signals. There
are several external trigger modes inside to support either single motion or conjunction motions, such as a raster
scan. For best convenience of control, the user can interact with the device by using the buttons and knob on the
front panel while observing the LCD display.
Figure 3.1 Outlook of PDXC Controller
Features
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Stages with open- and closed-loop operation are supported
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A modular linear amplifier paired with a high-power power supply outputs a peak current of 10 A to drive
the stage.
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The high current coupled with the optimized waveforms stably drive the stage as fast as 20 mm/s.
▪
Even at its highest speed, the optimized high-speed PID values allow the stage to move at ±2% speed
deviation in closed-loop mode.
▪
High positioning resolution up to 10 nm.
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With dynamic adjustment, the device stays at any precise position within a range of 10 nm in closed-loop
mode.
▪
Low time delay between devices when in daisy-chain mode.
3.2 Operation Principle
The controller mainly consists of 2 PCB boards, the MCU board, and the power board. The MCU board generates
a sawtooth waveform (Figure 3.2.1) while the power board magnifies the amplitude signal. The waveform is then
exported to the 15-pin D-SUB connector or SMC connector on the front panel to drive the different stages.
The stage uses a piezo inertial drive motor, which consists of three main parts: a flexure-coupled piezo actuator, a
friction element, and a slider (as seen in Figure 3.2.2). During the "stick" part of a cycle, the piezo slowly expands
under the ramp voltage, pushing the friction element and the slider forward in unison. During the "slip" part, the
drive voltage drops rapidly and the piezo element returns to its starting length, with the friction element "slipping"
