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A DC/DC converter arrangement includes an input terminal to receive a supply voltage, an output terminal to provide an output voltage and a switching arrangement, including a coil and at least two switches to provide a Buck-Boost conversion. The arrangement further includes a current detection circu

A DC/DC converter arrangement includes an input terminal to receive a supply voltage, an output terminal to provide an output voltage and a switching arrangement, including a coil and at least two switches to provide a Buck-Boost conversion. The arrangement further includes a current detection circuit which is coupled to the switching arrangement for sensing a coil current and a comparator, including a first input which is coupled to the output terminal and a second input which is coupled to an output of the current detection circuit. An output of the comparator is coupled to the switching arrangement. Furthermore, the arrangement includes a ramp generator which is coupled to the first or the second input of the comparator.

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1. A DC/DC converter arrangement, comprising: an input terminal to receive a supply voltage;an output terminal to provide an output voltage;a switching arrangement, comprising a coil, a first switch, a second switch, a third switch, and a fourth switch configured to provide the output voltage in a B

1. A DC/DC converter arrangement, comprising: an input terminal to receive a supply voltage;an output terminal to provide an output voltage;a switching arrangement, comprising a coil, a first switch, a second switch, a third switch, and a fourth switch configured to provide the output voltage in a Buck-Boost mode of operation, a Buck mode of operation or a Boost mode of operation of the DC/DC converter arrangement, wherein (i) the first switch comprises a p-channel field-effect transistor and a control terminal of the first switch is configured to receive a first control signal, (ii) the second switch comprises an n-channel field-effect transistor and a control terminal of the second switch is configured to receive the first control signal, (iii) the third switch comprises an n-channel field-effect transistor and a control terminal of the third switch is configured to receive a second control signal, and (iv) the fourth switch comprises a p-channel field-effect transistor and a control terminal of the fourth switch is configured to receive the second control signal;a current detection circuit which is coupled to the switching arrangement for sensing a coil current;a comparator, comprising: a first input which is coupled to the output terminal,a second input which is coupled to an output of the current detection circuit, andan output which is coupled to the switching arrangement to control at least one of the first switch, the second switch, the third switch or the fourth switch; anda ramp generator which is coupled to the first or the second input of the comparator and which generates a ramp signal such that: a slope of the ramp signal depends on a mode of operation of the DC/DC converter arrangement, the ramp signal rises during one switching phase of a plurality of switching phases of the Buck-Boost mode of operation, and the ramp signal is constant during three switching phases of the plurality of switching phases of the Buck-Boost mode of operation. 2. The DC/DC converter arrangement according to claim 1, comprising: a voltage divider which couples the output terminal to a reference potential terminal; anda first amplifier, comprising: a first input which is coupled to an output of the first voltage divider,a second input, andan output which is coupled to the first input of the comparator. 3. The DC/DC converter arrangement according to claim 1, the ramp generator comprising: a first input to receive a clock signal;a second input which is coupled to the output of the comparator to receive a comparator signal; anda third input to receive a Buck-Boost activation signal. 4. The converter arrangement according to claim 1, wherein: the first switch couples the input terminal of the DC/DC converter arrangement to a first terminal of the coil,the second switch couples the first terminal of the coil to a reference potential terminal,the third switch couples a second terminal of the coil to the reference potential terminal, andthe fourth switch couples the second terminal of the coil to the output terminal. 5. The DC/DC converter arrangement according to claim 1, comprising a logic circuit including: an input which is connected to the output of the comparator, andan output which is coupled to the switching arrangement for controlling the switching arrangement. 6. The DC/DC converter arrangement according to claim 3, the ramp generator comprising a first logic gate comprising: a first, a second and a third input which are coupled to the first, the second and the third input of the ramp generator, andan output to provide a ramp control signal which depends on the clock signal, the comparator signal and the Buck-Boost activation signal. 7. The DC/DC converter arrangement according to claim 5, comprising a mode selection circuit including: a first input which is coupled to the output terminal,a first output which is coupled to the logic circuit for providing a Buck-Boost activation signala second output which is coupled to the logic circuit for providing a Boost activation signal, anda third output which is coupled to the logic circuit for providing a Buck activation signal. 8. The DC/DC converter arrangement according to claim 6, the ramp generator comprising: a delay circuit with an input which is coupled to the first input of the ramp generator;a second logic gate, comprising: a first input which is coupled to the third input of the ramp generator,a second input which is coupled to an output of the delay circuit, andan output which is coupled to the first input of the first logic gate; anda flip-flop, comprising: a set input which is coupled to the second input of the ramp generator,a reset input which is coupled to the first input of the ramp generator, anda data output which is coupled to the second input of the first logic gate, wherein the first input of the ramp generator is coupled to the third input of the first logic gate. 9. The DC/DC converter arrangement according to claim 6, the ramp generator comprising: a ramp capacitor which couples a first node to a reference potential terminal;a discharging switch which couples the first node to the reference potential terminal and comprises a control terminal, the control terminal being coupled to the output of the first logic gate;a first current source which is coupled to the first node; andan output of the ramp generator at which the ramp signal is provided and which is coupled to the first node. 10. The DC/DC converter arrangement according to claim 6, the ramp generator comprising: a digital-to-analog converter including: an input which is coupled to an output of the first logic gate,an output which is coupled to a first node, andan output of the ramp generator at which the ramp signal is provided and which is coupled to the first node. 11. The DC/DC converter arrangement according to claim 9, the ramp generator comprising an output current source including: a control input which is coupled to the first node, andan output which is coupled to the output of the ramp generator. 12. The DC/DC converter arrangement according to claim 9, comprising a first resistor which couples the second input of the comparator to a reference potential terminal, wherein the output of the ramp generator is connected to the second input of the comparator. 13. The DC/DC converter arrangement according to claim 9, comprising a second amplifier including: a first input to which a reference voltage is supplied,a second input which is connected to the output of the ramp generator, andan output which is coupled to the second input of the first amplifier. 14. A method for DC/DC conversion, comprising: converting a supply voltage to an output voltage using a coil in a Buck-Boost mode of operation, a Boost mode of operation or a Buck mode of operation;controlling a switching arrangement comprising the coil, a first switch, a second switch, a third switch, and a fourth switch, wherein the switching arrangement is configured to provide the output voltage, wherein (i) the first switch comprises a p-channel field-effect transistor and a control terminal of the first switch is configured to receive a first control signal, (ii) the second switch comprises an n-channel field-effect transistor and a control terminal of the second switch is configured to receive the first control signal, (iii) the third switch comprises an n-channel field-effect transistor and a control terminal of the third switch is configured to receive a second control signal, and (iv) the fourth switch comprises a p-channel field-effect transistor and a control terminal of the fourth switch is configured to receive the second control signal;providing a current signal depending on a coil current;generating a ramp signal such that a slope of the ramp signal depends on a mode of operation, wherein the ramp signal rises during one switching phase of a plurality of switching phases of the Buck-Boost mode of operation, and the ramp signal is constant during three switching phases of the plurality of switching phases of the Buck-Boost mode of operation;comparing an error voltage which depends on the output voltage with a sense voltage which depends on the current signal and the ramp signal or comparing an error voltage which depends on the output voltage and the ramp signal with a sense voltage which depends on the current signal;providing a comparator signal as a function of the comparison; andcontrolling the Buck-Boost mode of operation of the conversion by the comparator signal. 15. The method according to claim 14, wherein the ramp signal is generated such that it rises in a ramp form during a switching phase of a plurality of switching phases of the Buck-Boost mode of operation and is constant during at least a further switching phase of the plurality of switching phases of the Buck-Boost mode of operation. 16. A DC/DC converter arrangement, comprising: an input terminal to receive a supply voltage;an output terminal to provide an output voltage;a switching arrangement, comprising a coil and at least two switches to provide the output voltage in a Buck-Boost mode of operation, a Buck mode of operation or a Boost mode of operation of the DC/DC converter arrangement;a current detection circuit which is coupled to the switching arrangement for sensing a coil current;a comparator, comprising: a first input which is coupled to the output terminal,a second input which is coupled to an output of the current detection circuit, andan output which is coupled to the switching arrangement to control at least one of the at least two switches;a ramp generator which is coupled to the first or the second input of the comparator and which generates a ramp signal such that a slope of the ramp signal depends on a mode of operation of the DC/DC converter arrangement, the ramp generator comprising: an output current source with an output which is coupled to an output of the ramp generator, wherein the output current source is configured as a voltage controlled current source, the output current source comprising a control input which is coupled to a first node of the ramp generator,a ramp capacitor which couples the first node to a reference potential terminal,a discharging switch which couples the first node to the reference potential terminal, anda first current source which is coupled to the first node, wherein the first current source is configured as a programmable current source such that the ramp capacitor is charged by a current, wherein a value of the current depends on the mode of operation such that the first current source provides a current with a first value when in the Buck-Boost mode of operation, a second value when in the Boost mode of operation, and a third value when in the Buck mode of operation. 17. A DC/DC converter arrangement, comprising: an input terminal to receive a supply voltage;an output terminal to provide an output voltage;a switching arrangement, comprising a coil and at least two switches to provide the output voltage in a Buck-Boost mode of operation, a Buck mode of operation or a Boost mode of operation of the DC/DC converter arrangement;a current detection circuit which is coupled to the switching arrangement for sensing a coil current;a comparator, comprising: a first input,a second input which is coupled to an output of the current detection circuit, andan output which is coupled to the switching arrangement to control at least one of the at least two switches;a first resistor which couples the second input of the comparator to a reference potential;a ramp generator which is coupled to the second input of the comparator and which generates a ramp signal such that a slope of the ramp signal depends on the mode of operation of the DC/DC converter arrangement, wherein the ramp generator provides the ramp signal in the form of a current to a first terminal of the first resistor;a voltage divider which couples the output terminal to the reference potential terminal; anda first amplifier, comprising: a first input which is coupled to an output of the first voltage divider,a second input, andan output which is coupled to the first input of the comparator,wherein the current detection circuit provides a current signal in the form of a current to the first terminal of the first resistor, andwherein the ramp signal and the current signal flow through the first resistor to the reference potential and generate a sense voltage which is applied to the second input of the comparator. 18. A DC/DC converter arrangement, comprising: an input terminal to receive a supply voltage;an output terminal to provide an output voltage;a switching arrangement, comprising a coil and at least two switches to provide the output voltage in a Buck-Boost mode of operation, a Buck mode of operation or a Boost mode of operation of the DC/DC converter arrangement;a current detection circuit which is coupled to the switching arrangement for sensing a coil current;a comparator, comprising: a first input which is coupled to the output terminal,a second input which is coupled to an output of the current detection circuit, andan output which is coupled to the switching arrangement to control at least one of the at least two switches; anda ramp generator which is coupled to the first or the second input of the comparator and which generates a ramp signal such that: a slope of the ramp signal depends on the mode of operation of the DC/DC converter arrangement, the ramp signal rises during one switching phase of a plurality of switching phases of the Buck-Boost mode of operation, and the ramp signal is constant during three switching phases of the plurality of switching phases of the Buck-Boost mode of operation,wherein the ramp generator provides the ramp signal in the form of a current and the current detection circuit provides a current signal in the form of a current.