Datalogger

Open, simple data logging for tests with our vacuum chambers.

Components

• AVR ATtiny424 µC
• ADS8688 8-channel ADC
• LTC1655 DAC
• one or two Instrumentation amplifiers for small differential signals (PT1000 bridges)
• LV-CMOS UART interface
• Raspberry Pi Host
• descoping population option: omit the µC and use the Raspberry Pi SPI.
• desoping population option: drop 16-bit ADC and DAC, instead, use what is integrated inside the µC with 10-bit resolution.
• Plugin connector to stack something else via SPI and/or I2C.

Features:

• Can be used stand-alone with Björns FDTI USB-RS232 boxes, or plugged onto a Raspberry Pi.
• 8 data acquisition channels, from 0…2.5V to ±10V inputs, 16 bit resolution.
• One analog output, ±10V, 16 bit resolution.

Board size

• Raspberry Pi

Tool chain

• Kicad 7 or lepton-schematic/gnetlist/pcb-gtk
• gerbv
• avr-gcc, avr-libc
• python

Alternative Design

• LPC2148 ARM µC like IRENA w/o FPGA
• Operated and Powered via USB
• Two boards (106×70mm) in one IRENA housing.