Abstract:
An electrical circuit (1) for conversion from differential to single-ended is described, comprising: a differential amplifier stage (2) having a first (IN+) and a second (IN") input; a first (5) and a different second charging circuit (6) of the differential stage that can be operatively coupled, respectively, with an output (OUT*) of the conversion circuit (1) and with an auxiliary output (AUXOUT*). The circuit also comprises a first (7) and a second (8) buffer circuit each functionally arranged between one of said outputs\and between one of said charging circuits. The buffer circuits being configured so as to minimise a difference between the relative impedances seen towards said outputs (OUT*, AUXOUT*).
Abstract:
An integrated buffer device (2) for a switched capacity circuit is described, comprising: - a buffer (7) having an output (OUT) for an output voltage dependent upon an input voltage (VIN) that can be supplied by a source (1) to the buffer device; - a capacitative switching component (C I ) that can be switched between a first and second condition in which it is connected, respectively, to the source and to the buffer to transfer the input voltage onto the output; said component being provided with a terminal (N2) having an associated stray capacity (C pi ). The device also comprises a charging and discharging device (SW CPIR , SW G ) configured to pre- charge the stray capacity at a reference voltage (REFM) before taking up the second condition and to pre-discharge the stray capacity before taking up the first condition.
Abstract:
The capacitors of a first array (10A') of sampling capacitors weighted in binary code are, connected between a first common circuit node (NB+) and an input terminal to be charged to the voltage (Vin) with respect to ground (Gnd) of a signal to be converted, and in accordance with BAR technique are then selectively connected with two differential reference terminals (Vrefp, Vrefm) .At the same time the capacitors of a second array (10B') equal to the first and all connected to a second node (NB-) are selectively connected to ground (Gnd) and the lower differential voltage terminal (Vrefm). The two nodes are connected to the respective inputs of a comparator (23"). A logic unit (17") controls the connections of the capacitors of the two arrays in accordance with a predetermined timing program and as a function of the output of the comparator (23"). Though the converter has a single-ended input, it behaves like a converter 20 with a differential input and therefore has an excellent immunity with respect to noise. Furthermore, it does not need either additional capacitors or a particularly sensitive comparator, so that it is characterized by low consumption and high speed and occupies a very small area of the integrated circuit of which it forms part.
Abstract:
An electrical circuit (1) for conversion from differential to single-ended is described, comprising: a differential amplifier stage (2) having a first (IN+) and a second (IN') input; a first (5) and a different second charging circuit (6) of the differential stage that can be operatively coupled, respectively, with an output (OUT*) of the conversion circuit (1) and with an auxiliary output (AUXOUT*). The circuit also comprises a first (7) and a second (8) buffer circuit each functionally arranged between one of said outputs\and between one of said charging circuits. The buffer circuits being configured so as to minimise a difference between the relative impedances seen towards said outputs (OUT*, AUXOUT*).
Abstract:
The capacitors of a first array (10A') of sampling capacitors weighted in binary code are, connected between a first common circuit node (NB+) and an input terminal to be charged to the voltage (Vin) with respect to ground (Gnd) of a signal to be converted, and in accordance with BAR technique are then selectively connected with two differential reference terminals (Vrefp, Vrefm) .At the same time the capacitors of a second array (10B') equal to the first and all connected to a second node (NB-) are selectively connected to ground (Gnd) and the lower differential voltage terminal (Vrefm). The two nodes are connected to the respective inputs of a comparator (23'). A logic unit (17') controls the connections of the capacitors of the two arrays in accordance with a predetermined timing program and as a function of the output of the comparator (23'). Though the converter has a single-ended input, it behaves like a converter 20 with a differential input and therefore has an excellent immunity with respect to noise. Furthermore, it does not need either additional capacitors or a particularly sensitive comparator, so that it is characterized by low consumption and high speed and occupies a very small area of the integrated circuit of which it forms part.
Abstract:
A circuit (20,20',20") includes a capacitance (Cvhv) coupled between a high voltage node (VHV) and ground, a laser diode (LD) having an anode coupled to the high voltage node (VHV) and a cathode coupled to an output node (OUT), and a current source (40) coupled between the output node (OUT) and ground. The current source (40) turns on based on assertion of a trigger signal and sinks current from the capacitance (Cvhv) to ground to thereby cause the laser diode (LD) to lase, and turns off based on deassertion of the trigger signal. A clamping circuit (22) is coupled between the output node (OUT) and the high voltage node (VHV), and clamps voltage at the output node (OUT) occurring when the current source (40) switches off.
Abstract:
A differential piezoelectric actuator-system (10) includes an inductor (L) and driver-circuit (11, 12) having switches (S1-S6) for transferring energy between first and second actuators (PZT1, PZT2) and the inductor, and between a voltage-supply node (Vbatt) and the inductor. Control circuitry (21) determines whether a next phase in which to operate the driver-circuit is a first charging-phase or a first recovery-phase. The first charging-phase includes operating the switches in: a first sub-phase to transfer energy from the first actuator to the inductor; a second sub-phase to transfer energy from the voltage supply node to the inductor; and a third sub-phase to transfer energy from the inductor to the second actuator. The first recovery-phase includes operating the switches in: a first sub-phase to transfer energy from the first actuator to the inductor; a second sub-phase to transfer energy from the inductor to the voltage supply node; and a third sub-phase to transfer energy from the inductor to the second actuator.
Abstract:
A DC-DC boost converter includes an inductor (L) coupled between an input voltage (Vin) and an input node (Nn), a diode (D1) coupled between the input node and an output node (No), and an output capacitor (C1) coupled between the output node and ground such that an output voltage (VBOOST) is formed across the output capacitor. A switch (Sw) selectively couples the input node to ground in response to a drive signal (Vdrive). Control loop circuitry (Vfbk, 15') includes an error amplifier (17') to generate an analog error voltage (Verr) based upon a comparison of a feedback voltage (Vfbk) to a reference voltage (Vref), the feedback voltage being indicative of the output voltage, a quantizer (21) to quantize the analog error voltage to produce a digital error signal (Err), and a drive voltage generation circuit (22) to generate the drive signal as having a duty cycle based upon the digital error signal.
Abstract:
A bridge driver circuit (104) applies a bias voltage across first (142) and second (144) input nodes of a resistive bridge circuit (102) configured to measure a physical property such as pressure or movement. A sensing circuit (185) senses a bridge current (Ipbridge, Inbridge) that flows through the resistive bridge circuit (102) in response to the applied bias voltage. A temperature dependent sensitivity of the resistive bridge circuit (102) is determined by processing the sensed bridge current. A voltage output at first (146) and second (148) output nodes of the resistive bridge circuit (102) is processed to determine a value of the physical property. This processing further involves applying a temperature correction in response to the determined temperature dependent sensitivity.
Abstract:
A method, comprising: - providing a load capacitance (C L ) having a charge node (104); - providing a set of energy storage capacitances (C 1 ), having respective charge nodes (101); - providing electronic switch circuitry (20) configured to be made selectively conductive to couple the charge node (104) of the load capacitance (C L ) to respective charge nodes (101) of energy storage capacitances (C 1 ) in the set of energy storage capacitances (C 1 ), wherein the electronic switch circuitry (20) comprise a switched current path (T, L) through a first transistor (TT 1 ) and a second transistor (TT 2 ) including junction diodes (BD1, BD2), wherein the first transistor (TT 1 ) has a current path therethrough between a first common node (SS) and the respective charge node (101) of an energy storage capacitance (C 1 ) in the set of energy storage capacitances (C 1 , C 2 ) and the second transistor (TT 2 ) has a current path therethrough between the first common node (SS) and the charge node (104) of the load capacitance (C L ), the first transistor (TT 1 ) and the second transistor (TT 2 ) having control terminals mutually coupled at a second common node (GG), the control terminals having a parasitic capacitance (C P ). The method comprises pre-charging the parasitic capacitance (C P ) of the control terminals of the first transistor (TT 1 ) and the second transistor (TT 2 ) mutually coupled at the second common node (GG) prior to making conductive the switched current path (T, L) through the first transistor (TT 1 ) and the second transistor (TT 2 ).