Csem Centre Suisse D'electronique Et De Microtechnique Sa&#x2014;recherche Et D&#xe9;veloppement

Christian Lotto

Peter Seitz

Simon Neukom

The current invention relates, inter alia, to charge pulse amplitude and time detecting circuits, offering very low amplitude and temporal noise, and overcoming noise performance limits in charge pulse detection circuits according to prior art. Embodiments of the present invention may include a sensing device delivering charge pulses onto a sense node, an active buffer buffering the voltage on the sense node with a low impedance, a recharge device removing signal charge from the sense node, a noise filter connected to the output of the active buffer transmitting signal voltage pulses while attenuating noise from the recharge device. Additional and alternative embodiments are specified and claimed.

Charge pulse detecting circuit

The present invention discloses a solid-state electric charge sensor () comprising at least one signal-readout circuit () that comprises a current source () and a column line (). The sensor also comprises at least one charge detector circuit () that is operatively coupled with the at least one signal-readout circuit (). The at least one signal-readout circuit () is characterized by further comprising at least one open-loop amplifier (), the input of which is operatively connectable with the at least one column signal line () and with the at least one current source (); at least one feedback line () that is operatively connectable with the output () of the at least one open-loop amplifier (); and operative to selectively form a negative feedback loop; and wherein the open-loop amplifier () has an inverting voltage gain.

Compact low noise signal readout circuit having at least one open-loop amplifier and method for operating thereof

The present invention refers, inter alia, to pixel circuits. The pixel circuit according to embodiments of the invention may include a photo-sensitive device having charge storage capability connected to a sense node. The pixel circuit may further include an inverting amplifier which is able to amplify a voltage from the sense node to a voltage on an output node of the amplifier, when being operated in open-loop configuration; and a reset switch being able to connect the input and output nodes of the inverting amplifier and thus to reset the inverting amplifier to an operating point providing high open loop gain by temporarily establishing negative feedback. Moreover, the pixel circuit may include a low-pass filter at the output node of the inverting amplifier for limiting the signal frequencies passing to the readout node to those frequencies that contain useful signal information. Additional and alternative embodiments are specified and claimed.

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Zurich, Switzerland

Christian Lotto