Abstract:
Disclosed herein are embodiments of an auto ranging system and method for an analog signal. A microprocessor is configured to digitally control the programmable gains of an operational amplifier based on the digital output of an A/D converter which may reside on or packaged along with the microprocessor. The amplifier receives a raw analog signal from a sensor and provides an amplified analog signal to the A/D converter. The gain of the amplifier generally corresponds to some range of the sensor signal. The A/D converter outputs a number of bits representative of the input signal. A microprocessor which is configured to digitally control the programmable gains of the amplifier receives and examines the output from the A/D converter and automatically adjusts the gain of the amplifier accordingly and as needed to keep or maintain the output from the A/D converter in a predetermined range.
Abstract:
Disclosed is an A/D converter with automatic gain control. The range to be selected is determined from the signal output values of the A/D converter. The circuit consists of an analog amplifier (3), connected to the A/D converter (2), which is followed by a digital amplifier (5). There is further another digital amplifier (9) before signal level measurement. All three amplifiers (3, 5, 9) have two positions. The circuit is used for a hearing aid.
Abstract:
A method of data acquisition at a magnetic resonance imaging (MRI) system is provided. The system receives at least a portion of raw data for an image, and detects anomalies in the portion of raw data received. When anomalies are detected, the system can correct those anomalies dynamically, without waiting for a new scan to be ordered. The system can attempt to scan the offending portion of the raw data, either upon detection of the anomaly or at some point during the scan. The system can also correct anomalies using digital correction methods based on expected values. The anomalies can be detected based on variations from thresholds, masks and expected values all of which can be obtained using one of the ongoing scan, previously performed scans and apriori information relating to the type of scan being performed.
Abstract:
Erfindungsgemäß wird ein Verfahren zur Entstörung eines Abtastprozesses zur Verfügung gestellt, wobei das Verfahren die Verfahrensschritte des Abtastens eines analogen Signals (16) mit einer Abtastfrequenz f (17) sowie des Bestimmens, ob eine Störamplitude (20) vorliegt, umfasst. Das Verfahren ist dadurch gekennzeichnet, dass bei Vorliegen einer Störamplitude (20) die Abtastfrequenz f (17) vergrößert oder verkleinert wird und das Verfahren erneut mit dem Verfahrensschritt des Abtastens des analogen Signals (16) mit der vergrößerten oder verkleinerten Abtastfrequenz beginnt. Ferner wird eine Vorrichtung zur Durchführung des Verfahrens zur Verfügung gestellt.
Abstract:
This disclosure describes techniques for detecting or predicting saturation of an analog-to-digital converter. The techniques analyze digital samples following analog to digital conversion, and count occurrences of specific values associated with a subset of bits within the digital samples. The specific subset of bits that are used detect or predict saturation may vary depending on the analog-to-digital converter and the number of bits in the digital samples. However, the techniques avoid the need to consider every bit in the digital samples, and rely only on a subset of bits (one or more), which can simplify the counting algorithms used in the saturation detection or prediction. Upon identifying a probable saturation state of the analog to-digital converter based on the counting, the techniques may de-boost the gain of an analog amplifier. This can effectively extend the dynamic range of the analog to digital converter.
Abstract:
The invention relates to a two-stage operational amplifier (400) in class AB for driving a load ( R LB , R LA ) comprising : - an input stage (401) comprising differential input terminals (I N , l p ) and a first differential output terminal (O1P) and a second differential output terminal (O1N) for providing a first differential driving signal (Out1P) and a second differential driving signal (Out1N), respectively; - an output stage (402) comprising a first output branch (403) having a first differential input terminal (I1P) operatively connected to the first differential output terminal (O1P) of the input stage (401) to receive the first differential driving signal (OUT1P) and a second output branch (404) having a second differential input terminal (I1N) operatively connected to the second differential output terminal (O1N) of the output stage (401) to receive the second differential driving signal (Out1N), - a control circuit (405) configured to control the output stage (402).
Abstract:
A microphone circuit has a clip detection circuit (30) which detects when an analogue to digital converter (ADC, 12) output has reached a threshold. A variable capacitance (34a, 34b, 34c, 34d), which functions as a variable input load associated with the microphone (11), is controlled based on the clip detection circuit output, the feedback is thus based on the ADC output level, and the processing of this signal can be implemented without requiring baseband processing of the signal - it can simply be based on a state of the ADC output.
Abstract:
A semiconductor die with an integrated circuit providing a signal conditioner (106) for a capacitive transducer (105), comprising: a gain stage (101) configured to receive an analogue transducer signal; an analogue-to-digital converter (102) coupled to receive a signal outputted from the gain stage (101) and to provide a digital signal. A feedback signal is provided via a digital-to-analogue converter (104) and a digital signal processor (103) that receives the digital signal; and the gain stage (101) is configured with a first input (107) and second input (108) coupled to receive the analogue transducer signal and the feedback signal, respectively.