Open platform, 32‐channel, portable, data‐logger with 32 PGA control lines for wearable medical device development. Issue 16 (1st July 2014)

• Record Type: Journal Article
• Authors: Gargiulo, G.D.; Bifulco, P.; Cesarelli, M.; McEwan, A.; Wabnitz, A.
• Is Part Of: Electronics letters. Volume 50:Issue 16(2014)
• Page Start: 1127
• Page End: 1129
• Publication Date: 2014-07-01
• Subjects: biomedical equipment -- data loggers -- low‐power electronics -- microprocessor chips -- biomedical electronics -- analogue‐digital conversion -- programmable circuits -- amplifiers -- printed circuits -- power supply circuits; PGA control line -- wearable medical device development -- low‐power portable data‐logging system -- NXP ARM processor -- LPC1768 -- linear technology octal analog‐to‐digital converter -- ADC -- LTC1857‐58‐59 -- touch‐screen display -- SHDC SD memory card -- SPI protocol -- user‐designed programmable gain amplifier -- GPL licence -- PCB -- galvanic isolation -- power supply data connection -- ADC channel -- word length 16 bit -- current 250 mA -- voltage 5 V -- storage capacity 32 Gbit; Electronics -- Periodicals; 621.381
• DOI: 10.1049/el.2014.1791
• Languages: English
• ISSNs: 0013-5194

Abstract

Abstract : A compact isolated low‐power 32‐channel 16‐bit data‐logging system around an NXP ARM processor (LPC1768) and four of the linear technology octal analogue‐to‐digital converters (ADCs) LTC1857/58/59 is designed. The system requires only 250 mA when powered at 5 V to run at full power (including a capacitive 2.8 inch touch‐screen display and 32 Gb SHDC SD memory card). The sample rate is configurable up to 1 k SPS per channel as well as voltage dynamic input up to ±10 V; additionally, 32 chip select lines (SPI protocol) individually addressable and controllable while sampling to configure user‐designed programmable gain amplifiers (PGAs) are available. Collaboration is being sought to improve the software capabilities, particularly to enrich the very basic user interface and to add wireless connectivity. The code is available (under the GPL licence) at our repository, the gerber file to reproduce the PCB is available (on the As‐Is basis) on request. The galvanic isolation between the power supply data connection and ADC channels makes the data‐logger also compatible with the main powered PCs, hence it is suitable for the implementation of medical devices at least for the prototyping and initial testing stages.