DE102016219230A1 - Circuit arrangement for driving at least one switch - Google Patents

Abstract

A circuit arrangement for driving at least one switch has an input (CON1) for receiving a drive signal, wherein one type of the drive signal is either a highside drive signal or a low side drive signal. The circuitry further comprises an output (CON2) for driving the at least one switch, and switching means connected to the input and the output, the switching means comprising means for converting a highside drive signal into a low side drive signal, so a low-side drive signal is output at the output for driving the at least one switch or has means for converting a low-side drive signal into a high-side drive signal, irrespective of a type of the drive signal, so that regardless of a type of drive signal at the output to Driving the at least one switch, a highside drive signal is output.

Description

The invention relates to a circuit arrangement for driving at least one switch.

The electronics of vehicles are tested in particular on test benches. For such test stands, there are often many different control devices which generate a drive signal for driving at least one switch.

The object underlying the invention is to provide a circuit arrangement for reliably driving at least one switch.

The object is solved by the features of the independent claim. Advantageous embodiments are characterized in the subclaims.

The invention is characterized by a circuit arrangement for driving at least one switch. The circuitry has an input for receiving a drive signal, one type of drive signal being either a highside drive signal or a low side drive signal. The circuit arrangement has an output for driving the at least one switch. The circuit has switching means connected to the input and the output. The switching means have means for converting a high-side drive signal into a low-side drive signal, so that a low-side drive signal is output independently of one type of the drive signal at the output for driving the at least one switch or means for converting from a low-side drive. Control signal in a high-side drive signal, so that regardless of a kind of the drive signal at the output for driving the at least one switch, a high-side drive signal is output.

The highside drive signal is in particular a drive signal for switching a switch, which is arranged between a voltage supply and a load.

The low-side drive signal is a drive signal for switching a switch disposed between a load and a ground.

The switch is in particular a relay.

By the switching means can be contributed to a reliable and flexible driving the at least one switch. This flexibility can be used, for example, for a test stand, since there may occur, for example, different output driver stages and due to the switching means does not always have to be created a new drive circuit.

According to an optional embodiment, the switching means have a bridge circuit.

By means of a bridge circuit, the means for converting from a high-side drive signal to a low-side drive signal or the means for converting from a low-side drive signal to a high-side drive signal can be realized in a simple and reliable manner.

According to a further optional embodiment, the switching means have toggle switches.

By means of a toggle switch, the means for converting from a high-side drive signal to a low-side drive signal or the means for converting from a low-side drive signal to a high-side drive signal can be realized in a very simple and cost-effective manner.

According to a further optional embodiment, the switching means have a change-over relay for galvanic isolation for the change of low-side drive signal in high-side drive signal or high-side drive signal in low-side drive signal.

By means of the change-over relay, a very robust switching from low-side drive signal to high-side drive signal or from high-side drive signal to low-side drive signal can be realized.

According to a further optional embodiment, the switching means have level stabilization means.

By means of the level stabilization means, it is possible to help prevent unwanted switching of the switch.

According to a further optional embodiment, the level stabilization means comprise at least one NOR gate and a resistor network.

Just by means of a NOR gate and a resistor network, a level stabilization can be achieved in a simple manner.

According to a further optional embodiment, the switching means have means for converting from a low-side drive signal into a high-side drive signal, so that regardless of the type of drive signal at the output for driving the at least one switch, a high-side drive signal is output.

According to a further optional embodiment, the circuit arrangement is designed to control four switches. As a result, four switches can be controlled with a compact circuit arrangement.

Embodiments of the invention are explained in more detail below with reference to the schematic drawing. It shows:

1 a circuit diagram of a circuit arrangement for driving at least one switch.

The 1 shows a circuit diagram of a circuit arrangement for driving at least one switch, in particular, as in 1 shown by four switches.

The circuit arrangement has a power supply connection, which is visualized with a plus sign. The circuit arrangement is supplied in particular with 12V.

Following the voltage supply connection, in particular a reverse polarity protection is provided. The reverse polarity protection includes, for example, a diode D1.

In addition, a fuse is provided to limit the current. The fuse F1 is, for example, a 1 amp fuse.

Then, in particular, a filter is provided at the reverse polarity protection in order to prevent disturbances from the circuit arrangement and for the fact that the circuit arrangement does not emit noise signals to the outside which would, for example, be violated by applicable EMC standards. The filter is, for example, an LC filter with the inductance L1 and the capacitor C1, wherein the inductance L1 has an inductance of 220 μF and the capacitor C1, for example, has a capacitance of 22 μF.

Subsequent to the filter, in particular, a switching converter U3 is provided, for example for the conversion of 12V to 5V, in particular to produce compatibility with TTL levels.

TTL stands for transistor-transistor logic. TTL circuits are designed especially for operation at a supply voltage of 5V with a deviation of 5%.

A further filter is then provided in particular to the switching converter U3 in order to prevent disturbances from the circuit arrangement and for the fact that the circuit arrangement does not emit interference signals to the outside which would, for example, be infringed by applicable EMC standards. The further filter is, for example, an LC filter with the inductance L2 and the capacitor C2, wherein the inductance L2 has an inductance of 100 μF and the capacitor C2, for example, has a capacitance of 0.22 μF.

The voltage supply filtered by the further filter is connected to an input CON1. The input CON1 serves as an interface to the outside world. By means of the input CON1, drive signals are fed in, one type of drive signal being either a high-side drive signal or a low-side drive signal.

Furthermore, information can be fed by means of the input CON1 as to whether the drive signals are a high-side drive signal or a low-side drive signal.

The circuit arrangement further comprises switching means connected to the input and an output, the switching means having means for converting a highside drive signal into a low side drive signal, so that whatever the type of drive signal at the output for driving the output at least one switch, a lowside drive signal is output or means for converting a Lowside drive signal into a highside drive signal, so that regardless of a type of drive signal at the output for driving the at least one switch, a highside drive signal is output. For this purpose, the switching means have, for example, a bridge circuit, a toggle switch and / or other suitable electronics.

In the 1 By way of example, switching means are shown which have means for converting a low-side drive signal into a high-side drive signal, so that a high-side drive signal is output regardless of a type of drive signal at the output for driving the at least one switch.

This is in the 1 the input CON1 is exemplarily coupled to a toggle switch S1 for switching between the highside drive signal and the low side drive signal.

Further, the input CON1 is coupled to a change-over relay Rel1, which provides galvanic isolation to switch from a highside drive signal to a low side drive signal. Parallel to the change-over relay Rel1 a freewheeling diode D2 is provided.

Subsequently, the lines are connected to a NOR gate U1, a resistor network R1 to R8 and a motor driver stage U2. The NOR gate U1 in conjunction with the resistor network R1 to R8 is used for level stabilization, so that the motor driver stage U2 can be controlled with a clean TTL level. The resistors R1 to R4 have, for example, 470 kΩ. The resistors R5 to R8 have, for example, 470 Ω.

The NOR gate U1 is, for example, additionally connected to a ground via further resistors R9 to R12. The further resistors R9 to R12 have, for example, 330 Ω.

The outputs of the motor driver stage U2 are connected, for example, to the output CON2 for driving the at least one switch, or as shown in FIG 1 shown to drive four switches.

By the in 1 shown circuit arrangement are supplied by means of the output CON2, for example, four relays always with high-side drive signals.

Since the motor driver stage U2 can drive about 1A current, for example, larger relays can be connected, which in turn can switch larger loads.

Advantageously, behind the output CON2 optocoupler stages are provided, which are used for relay control.

By the circuit arrangement shown, the four relays can be controlled by any signal source having either high-side or low-side switching behavior.

LIST OF REFERENCE NUMBERS

• C1, C2

  capacitor

  CON1

  entrance

  CON2

  output

  D1, D2

  diode

  F1

  fuse

  L1, L2

  inductance

  R1-R12

  resistance

  rel1

  changeover relay

  S1

  switch

  U1

  NOR gate

  U2

  Motor driver

  U3

  switching converters

Claims (8)

 Circuit arrangement for driving at least one switch having An input (CON1) for receiving a drive signal, one type of drive signal being either a highside drive signal or a low side drive signal, An output (CON2) for driving the at least one switch, Switching means connected to the input and the output, the switching means comprising means for converting a highside drive signal into a low side drive signal, such that regardless of a type of drive signal at the output for driving the at least one switch, a low side Control signal is output or have means for converting a low-side drive signal into a high-side drive signal, so that a high-side drive signal is output regardless of a type of the drive signal at the output for driving the at least one switch. Highside drive signal is a drive signal for switching a switch, which is arranged between a power supply and a load. Lowside drive signal is a drive signal for switching a switch, which is arranged between a load and a ground. Switch is in particular a relay.  Circuit arrangement according to Claim 1, in which the switching means have a bridge circuit.  Circuit arrangement according to Claim 1 or 2, in which the switching means have toggle switches.  Circuit arrangement according to one of the preceding claims, wherein the switching means comprise a changeover relay for galvanic isolation for changing low-side drive signal in high-side drive signal or high-side drive signal in low-side drive signal.  Circuit arrangement according to one of the preceding claims, wherein the switching means have level stabilization means.  Circuit arrangement according to claim 5, wherein the level stabilization means comprise at least one NOR gate (U1) and a resistor network (R1-R8).  Circuit arrangement according to one of the preceding claims, wherein the switching means comprise means for converting a Lowside drive signal into a high-side drive signal, so that regardless of the type of drive signal at the output for driving the at least one switch, a high-side drive signal is output. Circuit arrangement according to one of the preceding claims, wherein the Circuit arrangement for driving four switches is formed.

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