Patent ID: 7542262

Claim:
Apparatus for driving an electromagnetic load, said apparatus comprising: a power stage comprising at least one first transistor half-bridge and at least one second transistor half-bridges, said electromagnetic load being coupled between said first and second half-bridges, a first device and a second device suitable for driving in linear modality respectively said first and said second half-bridges, another device suitable for driving in pulse width modulation modality said first half-bridge, first switch means suitable for connecting said first half-bridge to said first device or to said other device in response to a control signal, second switch means suitable for connecting said second half-bridge to said second device in response to said control signal, said apparatus having an input signal, and a further device suitable for connecting said second half-bridge to a first reference voltage and to a second reference voltage when said first half-bridge is connected to said other device suitable for driving it in pulse width modulation modality, said first reference voltage being greater than said second reference voltage, wherein said first half-bridge comprises at least one first transistor having at least one first drivable terminal, and at least one second transistor having at least one second drivable terminal, said second half-bridge comprises at least one third transistor having at least one third drivable terminal, and at least one fourth transistor having at least one fourth drivable terminal, the first device and the second device driving in linear modality said first and said second half-bridges comprises said first device driving the first drivable terminal of the first transistor and the second drivable terminal of the second transistor of the first half-bridge, and said second device driving the third drivable terminal of the third transistor and the fourth drivable terminal of the fourth transistor of the second half-bridge, and the other device driving in pulse width modulation modality said first half-bridge comprises the other device driving the first drivable terminal of the first transistor and the second drivable terminal of the second transistor of the first half-bridge, and the further device connecting one of the third drivable terminal of the third transistor and the fourth drivable terminal of the fourth transistor to the first reference voltage and connecting the other of the third drivable terminal of the third transistor and the fourth drivable terminal of the fourth transistor to the second reference voltage.