Open Sourse Oscilloscope

Design overview

Hardware is built around Xilinx Artix-7 FPGA with an onboard RAM available for buffering samples (512 MB DDR3 SDRAM). All hardware settings are controlled via software GUI. USB connectivity is provided via Cypress’s FX3 USB 3.1 Gen1 chip. Hardware is USB powered which eliminates the need for additional power supply. Below you can find more information about individual hardware components.

Oscilloscope

Two analog channels are available as oscilloscope inputs. Both oscilloscope channels are protected against overvoltages up to +/- 50 V. Input coupling counters. Sine wave output is generated with the help of CORDIC algorithm which provides arbitrary frequency output. User can also provide a custom waveform sample data and upload it to FPGA internal memory (BRAM).

Digital GPIO (Logic Analyzer / Digital Pattern Generator)

12-bit digital interface is sampled at 250 Mhz and is logically divided into two 6-bit channel groups. Each channel group can be independently 1,25 V to 3,3 V, but inputs are designed to accept also 5 V. Selected interface voltage is also available on dedicated output pins and can be used as voltage supply. Custom digital samples for pattern generator can be uploaded to FPGA and internal clock divider is available to control the output frequency. It is also possible to override individual outputs with a logic 'LOW' or 'HIGH' at any time.

Specifications

Oscilloscope

• No. of Channels: 2
• Analog bandwidth (-3 dB): 100 Mhz
• Sampling rate, max.: 250 MSps dual ch. (500 MSps single ch.) / 2,0 Gsps with Equivalent-Time Sampling (ETS)
• Sampling rate, min.: 50 Sps
• Resolution: 10 bit
• Memory depth: 128.000.000 samples per channel
• Voltage ranges (with 1× probe): 10 mV, 20 mV, 50 mV, 100 mV, 200 mV, 500 mV, 1 V, 2 V per division
• Input Offset: adjustable
• Input coupling: DC, AC, GND
• Input impedance: 1 MΩ || 18 pF
• Max. input voltage: 20 V
• Overvoltage protection: +/- 50 V
• LED trigger indicator

Arbitrary Waveform Generator

• No. of Channels: 2
• Sampling rate: 200 Msps
• Resolution: 12 bit
• Output impedance: 50 Ω
• Output amplifier bandwidth: 30 Mhz
• Waveform shapes: Sin, Cos, Triangle, Saw, Ramp up/down, Delta, DC, Noise, Custom
• Custom waveform memory: 32.768 samples per channel
• Max out. Voltage: +/- 2,0 V
• Offset and Level adjustable
• Input protection: +/- 25 V
• Output protection: short-circuit

Logic Analyzer / Digital Pattern Generator

• No. of Channels: 12 (logic analyzer / pattern generator: 6-input / 6-output; 12-input; 12-output)
• Sampling rate: max. 250 Msps
• Interface voltage: Adjustable 1,25 V - 3,3 V in 256 steps
• LA Memory depth: 128.000.000 samples per channel
• Input Impedace (Logic Analyzer): 200 kΩ
• Output Impedance (Pattern Generator): 526 Ω
• Overvoltage protection: -5 V to +15 V
• Pattern Generator memory: 32.768 samples per channel
• Pattern Generator internal clock divider: Adjustable 32-bit (250 Mhz - 0,058 Hz)

Trigger

• Source: Analog Ch. 1, Analog Ch. 2, Digital GPIO (external), Generator Ch. 1, Generator Ch. 2
• Mode: Auto, Normal, Single (with Re-Arm)
• Pre-Trigger: Adjustable 0 - 99%
• Trigger Level: 0 - 100 %
• Trigger Level Hysteresis: Adjustable
• Trigger Holdoff: Adjustable 0 - 17 s (4 ns step size)
• Digital trigger: 4 stages (with delay counter for each stage)
• Digital trigger: selective channel masking (logic levels: '0', '1', 'Rising', 'Falling')