Abstract: A current mirror comprises first and second sets of transistors. each of the first and second sets is a matched set comprising a first transistor and a second transistor. For each set, the base of the first transistor is directly coupled to the base of the second transistor. For one of the first and second transistors of each set the base is directly coupled to the collector. The collectors of the first and second transistors of the first set are coupled, respectively, to the emitters of the first and second transistors of the second set in series. A current output of the current mirror is coupled between the collector of the second transistor of the first set and the emitter of the second transistor of the second set.

Abstract: A power supply circuit has parallel supply and control branches each with fuses, the power supply branch comprising at least one replaceable fuse. The supply branch is connected to one or more electrical components of an electrical device, such as the actuator and sensors of a printer, and the supply branch is connected to control or monitoring components. A circuit comprising lights indicates correct or faulty operation of the various parts of the supply circuit.

Abstract: A diagnostic device comprises a comparison section to compare an input voltage with a threshold voltage, wherein the input voltage is a power supply voltage for a component on a circuit board; and an indicator to provide an indication of the result of the comparison by the comparison section, the indication to render the circuit board identifiable to direct inspection, wherein the supply of power to the component is independent of the result of the comparison.

Abstract: An apparatus and methods for measuring a current flowing into an electrical device are described. In the apparatus, a current sensing circuit has at least one monolithic device, which in turn has a positive operating voltage and a negative operating voltage. The current sensing circuit is coupled to a power supply for the electrical device and the at least one monolithic device is arranged to enable a signal representative of the input current from the power supply to the electrical device to be output. The apparatus also has a power converter for converting a first voltage output by the power supply to a second voltage for supply as the positive operating voltage and a voltage clamp arranged to clamp the difference between the positive and negative operating voltages.

Abstract: A printed circuit board comprises at least one microstrip transmission line with a conductive solid reference plane and at least one conductive trace embedded in a dielectric substrate, and further comprises at least one conductive shielding layer having a lattice structure, wherein the conductive trace is arranged between the solid reference plane and the shielding layer.

Abstract: System and method for deglitching an input signal. An output signal may be delayed to generate a delayed signal, the delayed signal determining a guard time interval following a desired transition in the input signal, and a logic circuit is used to keep the output signal unchanged during the guard time interval, and to allow the output signal to equal the input signal outside the guard time interval, based on a value of the delayed signal.

Abstract: According to one example, there is provided a monitoring module for determining the status of electrical components in an array of N electrical components. The monitoring module comprises a resistance measurer to measure the resistance across a pair of diagnostic terminals, a comparator to compare the measured resistance with a set of reference resistances, and a diagnostic module to determine the status of at least one electrical component in the array based on the comparison.

Abstract: System and method for deglitching an input signal. An output signal may be delayed to generate a delayed signal, the delayed signal determining a guard time interval following a desired transition in the input signal, and a logic circuit is used to keep the output signal unchanged during the guard time interval, and to allow the output signal to equal the input signal outside the guard time interval, based on a value of the delayed signal.

Abstract: A bidirectional signal separation module includes a comparator having a first input node communicatively coupled to a bidirectional single-ended bus, a second input node communicatively coupled to a first voltage source, and an output node communicatively coupled to a unidirectional data transmission node; and a resistive network having a first node communicatively coupled to the second voltage source, a second node communicatively coupled to the bidirectional single-ended bus, a third node communicatively coupled to ground, and a fourth node communicatively coupled to an electronic switch. The electronic switch is configured to alternately couple the fourth node of the resistive network to the second voltage source or ground according to a voltage level on a unidirectional data receiving node.

Abstract: A bidirectional signal separation module includes a comparator having a first input node communicatively coupled to a bidirectional single-ended bus, a second input node communicatively coupled to a first voltage source, and an output node communicatively coupled to a unidirectional data transmission node; and a resistive network having a first node communicatively coupled to the second voltage source, a second node communicatively coupled to the bidirectional single-ended bus, a third node communicatively coupled to ground, and a fourth node communicatively coupled to an electronic switch. The electronic switch is configured to alternately couple the fourth node of the resistive network to the second voltage source or ground according to a voltage level on a unidirectional data receiving node.