Nxp B.v.

Koninklijke Philips Corporation N.v.

U.S. Philips Corporation

Fingerprint Cards Ab

Klaas-Jan De Langen

Johan Hendrik Huijsing

Antonius Martinus Jacobus Daanen

Gian Hoogzaad

Rolf Sundblad

Edmond Toy

Johan Frederik Witte

Martijn Bredius

Balwinder Singh

Emil Hjalmarson

Erik Säll

Guillaume Lebailly

Allan Olsson

Frederik Van Den Ende

Sybren Matthias Bouwhuis

Anthonius Bakker

A system comprising: a LDO regulator configured to receive a supply voltage and provide an output voltage based on a function of the supply voltage, the LDO regulator switchable between at least a first and second mode, wherein the first and second modes each define the output voltage provided to the output terminal based on different functions of the supply voltage; and a digital logic controller configured to select the mode of the LDO regulator by control signalling to the LDO regulator, the digital logic controller configured to receive power for the provision of the control signalling from the LDO regulator; wherein the LDO regulator comprises LDO start-up circuitry configured to cause the LDO regulator, during start-up, to default to a predetermined one of the first and second mode and the LDO start-up circuitry further configured to prevent the digital logic controller from controlling the mode of the LDO regulator.

System including a low drop-out regulator that provides supply voltage to digital logic controller configured to select mode of the low drop-out regulator

An apparatus comprising a first voltage domain circuit including a first circuit component configured to provide a first digital output signal; a second voltage domain circuit comprising a second circuit component; a level shifter arrangement configured to receive the first digital output signal and generate a second digital output signal based thereon with an increased voltage level of the high state, and provide said second digital output signal to the second circuit component; wherein the level shifter arrangement comprises at least one stage, the at least one stage comprising an arrangement of one or more diode-connected PMOS transistors, coupled to a CMOS inverter arrangement; the CMOS inverter arrangement of a first of the at least one stages configured to receive the first digital output signal and the CMOS inverter arrangement of a final stage of the at least one stages configured to output said second digital output signal.

Apparatus including a level shifter

An RF amplifier for implementation in SiGe HBT technology is described. The RF amplifier has a cascode stage comprising a common base (CB) transistor and a common emitter (CE) transistor arranged in series between a first voltage rail and a second voltage rail. An RF input is coupled to the base of the CE transistor and an RF output is coupled to the collector of the CB transistor. The RF amplifier includes a CB power-down circuit arranged between the base of the CB transistor and the second voltage rail and a CE power-down circuit arranged between the base of the CE transistor and the second voltage rail. In a power-down mode the CE power-down circuit couples the base of the common-emitter-transistor to the second voltage rail. The CB power-down mode circuit couples the base of the CB transistor to the second voltage rail via a high-ohmic path.

RF amplifier

A fingerprint sensing system comprising a device connection interface including a device reference potential input, a sensing arrangement, and sensing reference potential providing circuitry. The sensing arrangement includes multiple sensing structures and read-out circuitry connected to each of the sensing structures. The sensing reference potential providing circuitry provides a sensing reference potential to the sensing arrangement in the form of a sensing reference signal alternating between a first sensing reference potential and a second sensing reference potential, and comprises a first capacitor; a second capacitor; charging circuitry; and switching circuitry for alternatingly switching the sensing reference potential providing circuitry between a first state in which the first capacitor and the second capacitor are connected in parallel to the charging circuitry; and a second state in which the first capacitor and the second capacitor, when charged, are connected in series between the device reference potential input and the sensing arrangement.

Fingerprint sensing system with sensing reference potential providing circuitry

The present invention relates to a system for measuring a capacitor (C). A current source () is connected in parallel to the capacitor (C) between a supply plane (Vc) and groundfor providing a current to the capacitor (C). A voltage level-shift is connected between the supply plane (Vc) and the groundin parallel to the capacitor (C) and in parallel to the current source (I). The voltage level-shift senses a voltage across the electronic component (C) and provides a level-shifted output voltage Vin dependence thereupon. The voltage level-shift comprises a resistor (R) connected in series with a current source (II) and an output port interposed between the resistor (RI) and the current source (II). The current sources (I,) and () have opposite temperature coefficients such that the current provided to the electronic component is substantially constant.

System for diagnosing impedances having accurate current source and accurate voltage level-shift

An amplifier/driver () for a bus has an output transistor (M) that is controlled by a controlled current source (I). In a quiescent state, the output transistor is configured as part of a current mirror (M, M) that maintains a gate-source voltage on the output transistor above the threshold voltage of the output transistor, thereby providing a fast turnon turn-on time. In an active state, the controlled current source provides a substantially constant current to the output transistor to achieve a controlled slew-rate, then reduces the current to the output transistor when a desired output voltage level is achieved. To improve power efficiency, a second controlled current source (I) provides current to the output load when the desired output voltage level is achieved. To minimize transients, a class-AB control circuit () provides a minimum bias current to the output transistor, to prevent it from turning off when the desired output voltage level is achieved.

Turn-on bus transmitter with controlled slew rate

A digital blocking filter and filtering method are provided for a device receiving signals from a transmission line. The transmission line, which may comprise part of a complex bus system, is incompletely terminated, thereby resulting in a reflection signal within the line with transmission of a signal. The digital blocking filter includes a pulse generator for generating a masking pulse timed and of sufficient duration to substantially block at the device the reflection signal, and logic for combining the masking pulse and a received signal from the transmission line, thereby substantially blocking the reflection signal. Circuitry for handling reflection signals of various duration, as well as for substantially blocking a reflection signal on either a falling edge or a rising edge of a state change in the received signal are provided.

Digital filter circuit and method for blocking a transmission line reflection signal

An amplifier comprising an input stage (IP ) having a pair of inputs (INN,INI) for receiving a differential input signal (V ) and a pair of outputs (CQ ,CQ ) for delivering a differential intermediate signal in response to the differential input signal (V ); an intermediate stage (INT ) for converting the differential intermediate signal to a non-differential intermediate signal, which intermediate stage (INT ) comprises a current mirror (Q ,R ,Q ,R ) having an input branch (Q ,R ) and an output branch (Q ,R ) for receiving the differential intermediate signal; an output stage (OP ) having an input coupled to the output branch (Q ,R ) and having an output for delivering an output signal (V ) to an output (OP) of the amplifier; and means for stabilizing the amplifier. The means for stabilizing the amplifier comprises a capacitor (C ) coupled between the output (OP) of the amplifier and the input branch (Q ,R ), and provides a large bandwidth and low supply voltage amplifier.

Amplifier with stabilization means

A driving circuit provides a symmetric differential driving signal relative to one set of voltage potentials to a driver circuit that drives an output node to another set of voltage potentials. The differential driving signals from the driving system are equal and opposite to each other, thereby avoiding stray current flow between the driving system and the driven current mirrors. The transistors that provide the driving signal are continuously biased, using a weak bias in one logic state and stronger bias in the other state, to avoid hard-switching transients.

Level shifter with independent grounds and improved EME-isolation

An amplifier comprising an input stage (IP ) having a pair of inputs (INN,INI) for receiving a differential input signal (V ) and a pair of outputs (CQ ,CQ ) for delivering a differential intermediate signal in response to the differential input signal (V ); an intermediate stage (INT ) for converting the differential intermediate signal to a non-differential intermediate signal, which intermediate stage (INT ) comprises a current mirror (Q ,R ,Q ,R ) having an input branch (Q ,R ) and an output branch (Q ,R ) for receiving the differential intermediate signal; an output stage (OP ) having an input coupled to the output branch (Q ,R ) and having an output for delivering an output signal (V ) to an output (OP) of the amplifier; and means for stabilizing the amplifier. The means for stabilizing the amplifier comprises a capacitor (C ) coupled between the output (OP) of the amplifier and the input branch (Q ,R ). Thus, the current mirror (Q ,R ,Q ,R ) already available within the intermediate stage (INT ) is also used for signal inversion within a respective Miller loop. As a consequence, no current mirror is needed in the output stage (OP ) for the purpose of stabilizing the respective Miller loop. Thus, the inventive amplifier does not need a current mirror for driving the output stage (OP ). As a result the bandwidth of the amplifier is extended. Moreover, owing to the special manner in which the capacitor (C ) is coupled to the input branch (Q ,R ), the inventive amplifier does not need any differential stages in the output stage (OP ), which would limit the minimum supply voltage. The above-mentioned measures provide a large bandwidth and low supply voltage amplifier.

A reference circuit contains a PTAT (Proportional To Absolute Temperature) core. In the PTAT core there is a difference between the currents densities flowing through a first and second transistor. This difference results in a difference in junction voltage in the first and second transistor. The currents are adjusted by a local feedback loop in proportion to one another until the difference in junction voltage equals a voltage drop across a resistor. According to the invention the currents to both transistors are supplied by current sources, and the currents are adjusted by deviating a fraction of the supplied current from the transistors. This makes it possible to reference all control voltages for the transistors and the local feedback loop to the same supply connection, which increases the stability and power supply rejection of the circuit.

Growing community of inventors

Bergschenhoek, Netherlands

Klaas-Jan De Langen