Apple Inc.

Authentec, Inc.

Patrick J Landy

Dale R Setlak

Gordon Scot Franza

Giovanni Gozzini

Gregory Thomas Minteer

Jerry G Dooley

Jean-Marie Bussat

Dennis M Fischette, Jr

Pavel Mrazek

Shaobo Liu

Ondrej Konopka

Robert K Kong

Albert M Straub

Roger Lee Schenk

An apparatus includes an oscillator circuit that may generate a clock signal with a frequency that is based on a voltage level of a control node, and a charge pump circuit that includes a first current source and a second current source. The first current source may be coupled between a first supply node and a first circuit node. The second current source may be coupled between a second supply node and a second circuit node. The charge pump circuit may be configured to pre-charge the first and second circuit nodes to voltage levels that differ from the control node and the first and second supply nodes. In addition, the charge pump circuit may select, based on phase information, either the first or second circuit node, and then modify, based on a voltage level of the selected circuit node, a voltage level of the control node.

Energy-efficient charge pump design for phase-locked loops

A capacitive fingerprint sensor includes an array of capacitive sensing elements, readout circuitry electrically coupled to the array of capacitive sensing elements, a block first digital to analog converter (DAC), at least one second DAC, and at least one summing junction electrically coupled to the readout circuitry, the first DAC, and the at least one second DAC. The readout circuitry is adapted to read out pixel voltages from a group of each block of capacitive sensing elements. The first DAC is adapted to provide a block baseline voltage for each block of capacitive sensing elements. The second DAC is adapted to provide a pixel baseline voltage difference for one capacitive sensing element of each group of each block. The summing junction is adapted to subtract the received block baseline voltage and the received pixel baseline voltage difference from the corresponding pixel voltage of each row of each block.

Fixed pattern noise compensation techniques for capacitive fingerprint sensors

An electronic device may include finger biometric sensing pixels and a processor capable of cooperating with the finger biometric sensing pixels to generate a series of finger images at a progressively slower capture rate as a finger settling increases over time from initial placement of a user's finger adjacent the finger biometric sensing pixels. The processor may also be capable of cooperating with the finger biometric sensing pixels to determine a quality factor for each image in the series thereof, and select at least one image from the series thereof for matching and based upon the quality factor.

Electronic device generating finger images at a progressively slower capture rate and related methods

A finger biometric sensing device may include drive circuitry capable of generating a drive signal and an array of finger biometric sensing pixel electrodes cooperating with the drive circuitry and capable of generating a detected signal based upon placement of a finger adjacent the array of finger biometric sensing pixel electrodes. The detected signal may include a relatively large drive signal component and a relatively small sense signal component superimposed thereon. The finger biometric sensing device may also include a gain stage coupled to the array of finger biometric sensing pixel electrodes, and drive signal nulling circuitry coupled to the gain stage capable of reducing the relatively large drive signal component from the detected signal.

Finger biometric sensing device including drive signal nulling circuitry and related methods

A finger biometric sensing device may include an array of finger biometric sensing pixel electrodes and a gain stage coupled to the array of finger biometric sensing pixel electrodes. The finger biometric sensing device may also include error compensation circuitry that may include a memory capable of storing error compensation data. The error correction circuitry may also include a digital-to-analog converter (DAC) cooperating with the memory and coupled to the gain stage and capable of compensating for at least one error based upon the stored error compensation data.

Finger biometric sensing device including error compensation circuitry and related methods

A finger biometric sensing device may include an array of finger biometric sensing pixel electrodes and amplifiers coupled together in series and to be selectively coupled to respective ones of the array of finger biometric sensing pixels. The finger biometric sensing device may further include at least one coupling capacitor between an output of a given amplifier and a corresponding input of a next amplifier of the plurality thereof, and reset circuitry capable of selectively resetting the input of the next amplifier.

Finger biometric sensing device including coupling capacitor and reset circuitry and related methods

An electronic device may include an array of finger sensing pixels and data acquisition circuitry coupled to the array. The data acquisition circuitry may be capable of acquiring finger biometric data from each sub-array of the array, and acquiring spoof detection data from at least one of the sub-arrays in an interleaved fashion with the finger biometric data.

Electronic device including interleaved biometric spoof detection data acquisition and related methods

A finger sensing device may include an array of finger sensing pixels to receive a user's finger adjacent thereto. Each finger sensing pixel may include a finger sensing electrode. The finger sensing device may include a finger drive electrode configured to couple a drive signal through the user's finger to the array of finger sensing pixels. The finger sensing device may also include differential pixel measurement circuitry coupled to the array of finger sensing pixels and configured to generate a plurality of interpixel difference measurements for adjacent pairs of the finger sensing pixels.

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Cupertino, CA, United States of America

Patrick J Landy