An apparatus is provided that increases resolution of a resistance sensor. The apparatus may include a variable current source that produces a variable current in response to a current value. The apparatus may also include a variable resistance device that generates a variable voltage associated with the variable current. The variable resistance may have a low resistance value and a high resistance value. In addition, the apparatus may include a controller that receives a voltage value associated with the variable voltage and controls the current value in order to result in an increase in resolution of a range between the low resistance value and a high resistance value.

An apparatus is provided that increases resolution of a resistance sensor. The apparatus may include a variable current source that produces a variable current in response to a current value. The apparatus may also include a variable resistance device that generates a variable voltage associated with the variable current. The variable resistance may have a low resistance value and a high resistance value. In addition, the apparatus may include a controller that receives a voltage value associated with the variable voltage and controls the current value in order to result in an increase in resolution of a range between the low resistance value and a high resistance value.

The present invention relates to electrical measurement apparatus (10). The electrical measurement apparatus (10) comprises a measurement arrangement (20,24) configured to be disposed in relation to an electrical circuit (12,14,16,18) which bears an electrical signal, the measurement arrangement (20,24) being operative when so disposed to measure the electrical signal. The electrical measurement apparatus (10) further comprises a signal source (22) operative to apply a reference input signal to the measurement arrangement (20,24) whereby an output signal from the measurement arrangement comprises an electrical output signal corresponding to the electrical signal and a reference output signal corresponding to the reference input signal, the reference input signal having a substantially piecewise constant form which is repeated over each of plural cycles. The electrical measurement apparatus (10) yet further comprises processing apparatus (26) which is operative: to determine at least one cumulative representation, determination of the cumulative representation comprising summing plural received sections of the output signal, each of the plural received sections corresponding to at least a part and to a same part of the cycle of the reference input signal; and to determine at least one of: a transfer function for the measurement arrangement; a change in a transfer function for the measurement arrangement; and the electrical signal, in dependence on the at least one cumulative representation and the reference input signal.

The present invention relates to electrical measurement apparatus (10). The electrical measurement apparatus (10) comprises a measurement arrangement (20,24) configured to be disposed in relation to an electrical circuit (12,14,16,18) which bears an electrical signal, the measurement arrangement (20,24) being operative when so disposed to measure the electrical signal. The electrical measurement apparatus (10) further comprises a signal source (22) operative to apply a reference input signal to the measurement arrangement (20,24) whereby an output signal from the measurement arrangement comprises an electrical output signal corresponding to the electrical signal and a reference output signal corresponding to the reference input signal, the reference input signal having a substantially piecewise constant form which is repeated over each of plural cycles. The electrical measurement apparatus (10) yet further comprises processing apparatus (26) which is operative: to determine at least one cumulative representation, determination of the cumulative representation comprising summing plural received sections of the output signal, each of the plural received sections corresponding to at least a part and to a same part of the cycle of the reference input signal; and to determine at least one of: a transfer function for the measurement arrangement; a change in a transfer function for the measurement arrangement; and the electrical signal, in dependence on the at least one cumulative representation and the reference input signal.

An array of resistive sensor circuits may be used to gather sensor data. Each resistive sensor circuit may have a resistive sensor and an associated switch. Row decoder circuitry may supply rows of the sensor circuits with control signals on row lines. Capacitors associated with respective columns of the array may be provided with an initialization voltage. The control signals on the row lines may be used to turn on the switches in a selected row of the resistive sensor circuits and thereby discharge the capacitors through the resistive sensors of that row. Comparators may have first inputs coupled to the capacitors and second inputs that receive a reference voltage. A column readout circuit may have memory and processing circuitry that receives count values from a counter and that stores the count values in response to toggling output signals from the comparators.

A device for determining impedance at a data pin of a communication interface. In one embodiment, the device includes a current source configured to selectively inject a test current to the data pin. The device also includes a sensing circuit for sensing a first test voltage corresponding to a voltage at the data pin without the test current injected, and a second test voltage corresponding to another voltage at the data pin with the test current injected. The sensing circuit determines the impedance at the data pin based on the first test voltage and the second test voltage.

A device for determining impedance at a data pin of a communication interface. In one embodiment, the device includes a current source configured to selectively inject a test current to the data pin. The device also includes a sensing circuit for sensing a first test voltage corresponding to a voltage at the data pin without the test current injected, and a second test voltage corresponding to another voltage at the data pin with the test current injected. The sensing circuit determines the impedance at the data pin based on the first test voltage and the second test voltage.

A tool to measure resistance of a wire harness is disclosed herein. An example disclosed tool includes a connector with first and second plugs. The example disclosed tool also includes a resistor. A first terminal of the resistor is electrically coupled to the first plug. Additionally, the example disclosed tool includes a thermal switch attached to the resistor with a thermally conductive adhesive. A first terminal of the thermal switch is electrically coupled to a second terminal of the resistor, and a second terminal of the thermal switch is electrically coupled to the second plug.

A voltage dividing device includes: a plurality of resistive voltage dividing boards each being a plate-like board having a front face, the board having a plurality of conductor patterns arranged on the front face, the conductor patterns being connected in series with one another through capacitors and resistors connected in parallel on the front face of the board. The resistive voltage dividing boards are connected in series with one another through connecting members, and adjacent ones of the resistive voltage dividing boards are arranged so that a rear face of one of the adjacent resistive voltage dividing boards and a front face of the other resistive voltage dividing board face each other and that the conductor patterns arranged on the front face of the one resistive voltage dividing board are disposed oppositely from the conductor patterns arranged on the front face of the other resistive voltage dividing board.

A voltage dividing device includes: a plurality of resistive voltage dividing boards each being a plate-like board having a front face, the board having a plurality of conductor patterns arranged on the front face, the conductor patterns being connected in series with one another through capacitors and resistors connected in parallel on the front face of the board. The resistive voltage dividing boards are connected in series with one another through connecting members, and adjacent ones of the resistive voltage dividing boards are arranged so that a rear face of one of the adjacent resistive voltage dividing boards and a front face of the other resistive voltage dividing board face each other and that the conductor patterns arranged on the front face of the one resistive voltage dividing board are disposed oppositely from the conductor patterns arranged on the front face of the other resistive voltage dividing board.