Abstract:
The present invention provides a driving circuit (100) in particular for driving a laser diode (700) or a modulator, at data speed in the order of Gb/s. The driving circuit (10) has a low-voltage, high-speed output stage capable of driving efficiently a laser diode (700) or a modulator. The driver circuit (10) comprises a chain of circuits, said chain comprising a slew-rate control circuit, at least one translinear amplifier (200, 201, 202), a push/pull stage (300), and an output stage (400) for driving the load current. Due to its versatility, the driver can be used in other applications e.g. line drivers, cable drivers, high-speed serial interfaces for back-plane interconnect, etc. The driver can work at low supply voltages, e.g. 3.3V nominal down to 2.7V, with high power efficiency. One major clue is to use entirely the large signal current produced by the output stage, e.g. in the driven laser diode, without wasting current in supply lines.
Abstract:
A frequency divider comprising a first flip-flop (M1, M2, M3, M4) having a first clock input (CI) for receiving a clock signal, the flip-flop further comprising a first set input (Q4) and a first non-inverted output (Q1). The frequency divider further comprises a second flip-flop (M'1, M'2, M'3, M'4) having a second clock input (Cl) for receiving a second clock signal that is substantially in anti-phase with the clock signal inputted into the first clock input (Cl), a second set input coupled to the first non-inverted output (Q1), a second non-inverted output (Q2) and a second inverted output (Q2), the second inverted output (Q2) being coupled to the first set input (Q4).
Abstract:
A prescaler, comprising a first flip-flop (F1) coupled to a second flip-flip (F2). Each flip-flop comprises a latch (M1, M2, M3, M4) having a first input (R) and a second input (S) coupled to respective first NOR circuit (M8, M9, M10) and second NOR circuit (M5, M6, M7).
Abstract:
The present invention relates to a polar modulation apparatus and method, in which a polar-modulated signal is generated based on separately processed phase modulation (PM) and amplitude modulation (AM) components of an input signal. An amplified polar modulated output signal is generated in accordance with the phase modulation and amplitude modulation components by using a differential power amplifier circuitry(30) and supplying an amplified phase modulation component to a differential input of the differential power amplifier circuitry(30). A bias input of the differential power amplifier circuitry(30) is controlled based on the amplitude modulation component, so as to modulate a common-mode current of the differential power amplifier circuitry(30). Thereby, a new concept of a polar modulator with static DC-DC converter and power and/or efficiency and/or linearity controlled output power amplifier can be achieved.
Abstract:
A broadband amplifier (2) for receiving radio frequency signals from an antenna (4) is disclosed. The amplifier comprises a first amplifier stage (6) for receiving an input voltage signal, and a first feedback stage (12) for providing a feedback link between an input and an output of the first amplifier stage (6). A second amplifier stage (10) is connected to an output of the first amplifier stage (6) and a second feedback stage (16) provides a feedback link from an output of the second amplifier stage to an input of the first amplifier stage. An output voltage signal is provided at an output terminal (22) of an output stage (20).
Abstract:
Devices (101-105) comprising latches (1-3) with tracking circuits (4) for, in tracking modes, tracking data signals and with deciding circuits (5) for, in deciding modes, deciding about the data signal can use their available time more efficiently by, in the tracking modes, preparing the deciding circuits (5). Thereto, the deciding circuits (5) are not to be switched between disabled/enabled situations, but are to be kept enabled. The tracking circuits (4), in the tracking modes, supply signal values derived from the data signals to the deciding circuits (5), and the deciding circuits (5), in the deciding modes, amplify the signal values. The tracking circuits (4) comprise diodes (21,22) to allow reduced voltage swings in the data signals to be sufficient for proper performances of the latch (1-3). Such reduced voltage swings allow the latches (1-3) to perform at higher speeds. The parasitic capacitors present between the cathodes of the diodes (21,22) form capacitances for storing the signal values and allow the deciding circuits (5) to be prepared.
Abstract:
A latch circuit (1) comprising, a differential input with an inverting input (D+) and a non-inverting input (D-). The latch further comprises a differential output with an inverting output (Q+) and a non-inverting output (Q-). One of the outputs (Q-) is coupled to one of the inputs input (D+) having an opposite polarity. The latch further comprises a control input for receiving a control signal (V cM ) for determining a threshold for an input signal (In) such that if the input signal is at larger than the threshold the non-inverting output s in a HIGH logic state and in a LOW state if the input signal is smaller than the threshold, respectively.
Abstract:
A calibrating system for a receiver receiving an input signal (Rf) having an input frequency (fRf) and working in a receiving mode (R) and in a calibrating mode (C) comprising an intermediate frequency circuit (IF) coupled to a first mixer and comprising a bulk acoustic wave filter (BAW) determining the intermediate frequency (BAWf). The calibrating system further comprises a level detecting circuit (LD) coupled to the intermediate frequency circuit (IF) via a first switch (S1) in the calibrating mode (C) for determining an amplitude of the intermediate frequency signal. The receiver includes a tuning control processor (TC) coupled to the first synthesizer (LO1) and to the second synthesizer (L02) controlling the frequencies generated by said synthesizers (LO1, L02). A level detecting circuit (LD) is coupled to the intermediate frequency circuit (IF) for determining an amplitude of the intermediate frequency signal and providing a signal indicative for said amplitude to the tuning control processor (TC). The system further comprises a register (Reg) coupled to the tuning control processor (TC) for memorizing a number corresponding to the intermediate frequency (BAWf), the number being used as a correction factor for the first and second synthesizers (LO I, L02) in the receiving mode (R).
Abstract:
The invention relates to an electronic device for controlling a controlled oscillator. The electronic device provides a control input for supplying a control signal for tuning the oscillating frequency of the oscillator. Further the electronic device provides a transconductor having a transfer function in the frequency range with a substantially first- order high frequency roll off characteristic. The transconductor is adapted to be coupled to a tank circuit (L0, C0) and to act as a variable capacitance, such that the control signal controls the value of the variable capacitance of the transconductor for tuning the oscillating frequency of the controlled oscillator.
Abstract:
The present invention relates to a differential oscillator circuit and a method of controlling the frequency of an oscillator signal. An enhanced frequency tuning mechanism is provided for controlling the frequency of the oscillator signal. The frequency tuning mechanism comprises first frequency control circuitry for controlling the threshold voltage of respective load transistors (M3, M4) of the differential oscillator circuit, and second frequency control circuitry for controlling at least one of a common-mode current (I BIAS ) flowing through branches of said differential oscillator circuit, a tail current (I TUNE ) of an additional feedback circuit (M5, M6) cross-coupled between the drains of a differential transistor stage (Ml, M2) of said differential oscillator and respective gates of said load transistors (M3, M4), and a voltage applied at a middle point of a tapped coil of a resonating circuit of the differential oscillator circuit. Thereby, a linear fine tuning characteristic can be obtained, where the tuning mechanism may for example work as a "gear-box" by stepping coarsely with the first frequency control circuitry through fine intervals generated by the second frequency control circuitry.