Velleman PCSGU250

Velleman PCSU250

The [1] is an inexpensive USB-based oscilloscope. It has 2 channels, an analog bandwidth of 12MHz and 25MS/s sampling rate.

See Velleman PCSU250/Info for more details (such as lsusb -vvv output) about the device. Vellemann PCSGU250/USB Control]

Hardware

Control logic

• Xilinx XC3S50 50K-gate FPGA
• 50MHz crystal: 50.000 Y0KE (clock source for the Xilinx FPGA)
• Microchip PIC18LF2450-I/SP 8-bit microcontroller

USB interface

• inluded in the PIC

Analog frontend

• 4 x SIR-S4-105A IZ Goodsky 5V relay (2 per input channel)
• 2 x Texas Instruments OPA2354 op-amps
• 1 x Analog Devices AD9288BST-40 Dual 8-bit 40MSPS A/D converters

Power

• 3 x Texas Instruments TPS766xx voltage regulators (IC19=1V, IC20=2.5V, IC21=3.3V)

Trigger Level

• 74HCT4051D 8-channel analog multiplexer/demultiplexer with 15 resistors, is that a R2R DAC??? I would guess this one is for the trigger level

Signal Generator

• DAC0800LCM 8-Bit Digital-to-Analog Converter Settling Time 0.1 µs, does that mean max. 10Mhz Sample rate?
• TL081C JFET OPAMP
• lm6172 Dual High Speed, Low Power, Low Distortion Voltage Feedback Amplifiers 100Mhz GBW

Photos

• 

  PCB, front

• 

  PCB, back

• 

  signal generator or trigger circuit?

• 

  output stage

• 

  chunk of rusty metal for weighte

• 

  output stage

Protocol

https://bitbucket.org/abbradar/scope/src http://forum.velleman.eu/viewtopic.php?f=10&t=3586&start=15 https://app.box.com/s/cxybc16r7o5kqb65u6ct