EP 2193339 A1 20100609 - FIELD DEVICE HAVING AN ANALOG OUTPUT
Title (en)
FIELD DEVICE HAVING AN ANALOG OUTPUT
Title (de)
FELDGERÄT MIT EINEM ANALOGAUSGANG
Title (fr)
APPAREIL DE TERRAIN À SORTIE ANALOGIQUE
Publication
Application
Priority
- EP 2008062946 W 20080926
- DE 102007046560 A 20070928
Abstract (en)
[origin: WO2009043821A1] The invention relates to a field device having an analog output, especially a measuring transducer (1) for process instrumentation having a 4-20 mA interface as the analog output (7). For digital-to-analog conversion, a digital value is split into a digital coarse portion and a digital fine portion. Depending on the digital coarse portion, a first analog signal (V1) is generated using a pulse width modulator (BUF1) having a low path filter (TP1) mounted downstream thereof, which signal is above the analog output signal (VOUT), and a second output signal (V2) using a pulse width modulator (BUF2) having a low path filter (TP2) mounted downstream thereof, which signal is below the analog output signal(VOUT). Both analog signals (V1, V2) are guided to a third pulse width modulator (SW1) which is controlled depending on the digital fine portion, a low-pass filter (TP3) being mounted downstream thereof. The invention allows provision of an analog output signal (VOUT) having high resolution and good dynamic properties. The field device is further characterized by a digital-to-analog converter that can be produced with especially little complication.
IPC 8 full level
G01D 3/024 (2006.01); G08C 13/02 (2006.01); G08C 19/02 (2006.01); H03M 1/00 (2006.01); H03M 1/68 (2006.01); H03M 1/86 (2006.01)
CPC (source: EP US)
G01D 3/024 (2013.01 - EP US); H03M 1/68 (2013.01 - EP US); H03M 1/822 (2013.01 - EP US)
Citation (search report)
See references of WO 2009043821A1
Designated contracting state (EPC)
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR
Designated extension state (EPC)
AL BA MK RS
DOCDB simple family (publication)
DE 102007046560 A1 20090402; CN 101809413 A 20100818; EP 2193339 A1 20100609; US 2010302085 A1 20101202; WO 2009043821 A1 20090409
DOCDB simple family (application)
DE 102007046560 A 20070928; CN 200880109459 A 20080926; EP 08834820 A 20080926; EP 2008062946 W 20080926; US 68043208 A 20080926