A reading circuit for a charge-retention circuit stage is provided with a storage capacitor coupled between a first biasing terminal and a floating node, and a discharge element coupled between the floating node and a reference terminal. The reading circuit further has an operational amplifier having a first input terminal that is coupled to the floating node and receives a reading voltage, a second input terminal receives a reference voltage, and an output terminal on which it supplies an output voltage, the value of which is a function of the comparison between the reading voltage and the reference voltage and indicative of a residual charge in the storage capacitor. A shifting stage shifts the value of the reading voltage of the floating node, before the comparison is made between the reading voltage and the reference voltage for supplying the output voltage.

A reading circuit for a charge-retention circuit stage is provided with a storage capacitor coupled between a first biasing terminal and a floating node, and a discharge element coupled between the floating node and a reference terminal. The reading circuit further has an operational amplifier having a first input terminal that is coupled to the floating node and receives a reading voltage, a second input terminal receives a reference voltage, and an output terminal on which it supplies an output voltage, the value of which is a function of the comparison between the reading voltage and the reference voltage and indicative of a residual charge in the storage capacitor. A shifting stage shifts the value of the reading voltage of the floating node, before the comparison is made between the reading voltage and the reference voltage for supplying the output voltage.

A reading circuit for a charge-retention circuit stage is provided with a storage capacitor coupled between a first biasing terminal and a floating node, and a discharge element coupled between the floating node and a reference terminal. The reading circuit further has an operational amplifier having a first input terminal that is coupled to the floating node and receives a reading voltage, a second input terminal receives a reference voltage, and an output terminal on which it supplies an output voltage, the value of which is a function of the comparison between the reading voltage and the reference voltage and indicative of a residual charge in the storage capacitor. A shifting stage shifts the value of the reading voltage of the floating node, before the comparison is made between the reading voltage and the reference voltage for supplying the output voltage.

Some embodiments of the invention relate to a time measurement circuit for an incoming signal. In some embodiments, the time measurement circuit has a comparator stage, for generating a comparator output signal depending on a fulfillment of a criterion by the incoming signal, wherein exceeding or falling below a threshold value is defined as the criterion. Furthermore, a digitization stage is provided, for sampling, which is performed at a defined sampling rate, of an input signal fed to the digitization stage and converting it into digital data containing sampled values for the input signal, and an evaluation unit for determining a chronological location for the incoming signal by evaluating the digital data.

Some embodiments of the invention relate to a time measurement circuit for an incoming signal. In some embodiments, the time measurement circuit has a comparator stage, for generating a comparator output signal depending on a fulfillment of a criterion by the incoming signal, wherein exceeding or falling below a threshold value is defined as the criterion. Furthermore, a digitization stage is provided, for sampling, which is performed at a defined sampling rate, of an input signal fed to the digitization stage and converting it into digital data containing sampled values for the input signal, and an evaluation unit for determining a chronological location for the incoming signal by evaluating the digital data.

A method and system for controlling a commercial transaction is presented. An article of manufacture has a time cell that is read by an electronic apparatus. In response to a determination of a state of the time cell by the electronic apparatus, usage of the article of manufacture in a commercial transaction is enabled or denied based on the determined state of the time cell. The expiration period of a time cell controls the time period during which the commercial transaction is enabled or is denied to be performed; an unexpired time cell may both enable or deny performance of a commercial transaction, and an expired time cell may also both enable or deny performance of a commercial transaction. The time cell may be used to restrict the usage period of a coupon, a promotional offer, a pre-paid service, or some other commercial transaction that involves an article of manufacture.

A method and system for controlling a commercial transaction is presented. An article of manufacture has a time cell that is read by an electronic apparatus. In response to a determination of a state of the time cell by the electronic apparatus, usage of the article of manufacture in a commercial transaction is enabled or denied based on the determined state of the time cell. The expiration period of a time cell controls the time period during which the commercial transaction is enabled or is denied to be performed; an unexpired time cell may both enable or deny performance of a commercial transaction, and an expired time cell may also both enable or deny performance of a commercial transaction. The time cell may be used to restrict the usage period of a coupon, a promotional offer, a pre-paid service, or some other commercial transaction that involves an article of manufacture.

A reading circuit for a charge-retention circuit stage is provided with a storage capacitor coupled between a first biasing terminal and a floating node, and a discharge element coupled between the floating node and a reference terminal. The reading circuit further has an operational amplifier having a first input terminal that is coupled to the floating node and receives a reading voltage, a second input terminal receives a reference voltage, and an output terminal on which it supplies an output voltage, the value of which is a function of the comparison between the reading voltage and the reference voltage and indicative of a residual charge in the storage capacitor. A shifting stage shifts the value of the reading voltage of the floating node, before the comparison is made between the reading voltage and the reference voltage for supplying the output voltage.

A reading circuit for a charge-retention circuit stage is provided with a storage capacitor coupled between a first biasing terminal and a floating node, and a discharge element coupled between the floating node and a reference terminal. The reading circuit further has an operational amplifier having a first input terminal that is coupled to the floating node and receives a reading voltage, a second input terminal receives a reference voltage, and an output terminal on which it supplies an output voltage, the value of which is a function of the comparison between the reading voltage and the reference voltage and indicative of a residual charge in the storage capacitor. A shifting stage shifts the value of the reading voltage of the floating node, before the comparison is made between the reading voltage and the reference voltage for supplying the output voltage.

Mechanisms for controlling a commercial transaction is presented. An article of manufacture has a time cell that is read by an electronic apparatus. In response to a determination of a state of the time cell by the electronic apparatus, usage of the article of manufacture in a commercial transaction is enabled or denied based on the determined state of the time cell. The expiration period of a time cell controls the time period during which the commercial transaction is enabled or is denied to be performed; an unexpired time cell may both enable or deny performance of a commercial transaction, and an expired time cell may also both enable or deny performance of a commercial transaction. The time cell may be used to restrict the usage period of a coupon, a promotional offer, a pre-paid service, or some other commercial transaction that involves an article of manufacture.