Gwyscope documentation

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Gwyscope DSP is a shorthand for three boards combo:

Red Pitaya STEMlab 125-14 (PCB Red Pitaya)
Mainboard (PCB CMIPITAYA)
20-bit DAC board (PCB CMIDAC11001)

Although we designed the boards to be connected in a stack to enhance capabilities of the Red Pitaya, other use cases are possible. For example only Red Pitaya board and Mainboard might be used to enhance Red Pitaya with many channels high bit-depth converters or the 20-bit DAC board can be solely controlled by Arduino.

Specifications

Basic

Processor:	dual core ARM Cortex A9
FPGA:	Xilinx Zynq 7010 SOC
RAM:	512 MB
System memory:	Micro SD up to 32 GB
Power consumption (max):	5 V, 2 A; ±12 V, 1 A
Communication interfaces:	RS232, I2C, 1 Gb Ethernet, USB 2.0
Form factor:	Eurocard (160 mm x 100 mm)

Fast ADC

Number of channels:	any 2 of 16 available inputs (selected using multiplexer)
Voltage range:	±1 V / ±10 V software adjustable
Sample rate:	125 MS/s
ADC resolution:	14 bits
Input coupling:	DC
Bandwidth (-3 dB):	10 MHz / 50 MHz*

* if input buffers bypassed by jumpers

Fast DAC

Number of channels:	2
Voltage range:	±10 V / ±1 V*
Sample rate:	125 MS/s
ADC resolution:	14 bits
Bandwidth (-3 dB):	DC - 1 MHz / DC - 50 MHz*

* if output buffers bypassed by jumpers

Auxiliary ADC

Number of channels:	16, simultaneous sampling
Voltage range:	±10 V
Sample rate:	>1 kS/s (depending on configuration)
ADC resolution:	18 bits
Input coupling:	DC
Oversampling:	1 - 64 (software adjustable)

Auxiliary DAC

Number of channels:	16
Voltage range:	±10 V
Sample rate:	>1 kS/s (depending on configuration)
DAC resolution:	16 bits

Hi-resolution DAC

Number of channels:	3
Voltage range:	±5 V, ±10 V, 0-5 V, 0-10 V (jumper adjustable)
Sample rate:	>30 kS/s (depending on configuration)
DAC resolution:	20 bits

Low-resolution ADC

Number of channels:	4
Voltage range:	0 - 3.5 V
Sample rate:	100 kS/s
ADC resolution:	12 bits
Input coupling:	DC

Digital outputs

Number of outputs:	4 + 6 (via IO expander)
Voltage level:	1.8 V / 3.3 V (IO expander)

Features

Feedback loop for contact and non-contact optical lever based SPM probes
Feedback loop for self-sensing probes (e.g. Akiyama) using FM detection via PLL
Z piezo signal output through 20-bit DA converter
16 simultaneously sampled 18-bit inputs
16 independent 16-bit outputs
Reconfigurable input and output voltage ranges
Two lock-in amplifiers with signal generators 500 Hz to 2 MHz
Third internal generator for lock-in operation at other than generating frequency
Lateral motion control using serial interface or two 20 bit DA converters
Variety of ways to perform non-raster and adaptive measurements, including use of Gwyscan library and Lua interface
Digital PLL feedback - configurable PLL range up to full range of the lock-in signal generators; configurable lock-in amplitude and phase output filter 100 Hz - 100 kHz SPM modes
Atomic Force Microscopy and Force-Distance curves acquisition
Magnetic Force Microscopy in the lift mode
Conductive AFM, Scanning Thermal Microscopy and other additional signal based SPM methods
AM Kelvin Probe Force Microscopy
Force Distance curves and Force Volume data acquisition