Abstract:
In multiphase driving systems of electric motors in a switching mode employing distinct integrated half-bridge output stages, the use of multiple external components for each integrated half-bridge stage to implement functions of adjustment of the switching dead-time and of disabling/enabling of the half-bridge stage can be avoided and an improved matching obtained by using single external components connected in common to the dedicated pins of all the distinct integrated half-bridge output stages. This is achieved by duplicating the disabling comparator, respectfully for the power transistor of the pull-up branch and for the power transistor of the pull-down branch in each integrated half-bridge stage.
Abstract:
A high side circuit is described which comprises at least one power device (1) having a first non drivable terminal (D) connected to a supply voltage (Vcc), at least one load (2) connected between a second non drivable terminal (S) of the power device (1) and ground, and driving circuitry (10). The driving circuitry (10) comprises suitable dimensioned transistors (M1, M2, M3) which are connected to each other and to a higher voltage (Vboot) than the supply voltage (Vcc) in order to control the turning on and the turning off of the power device (1) and to minimize the potential difference between the second non drivable terminal (S) and a drivable terminal (G) of the power device (1) during the turning off state to avoid the re-turning on of the same power device.
Abstract:
The present invention relates to a current (I) control method for drive systems of multi-phase brushless motors, in particular at phase switching, wherein the motor coils (1,2,3) led to a common node (D) are driven by applying a respective drive voltage to the free end (A,B,C) of each coil (1,2,3) via corresponding power stages (4,5,6). The method comprises switching the current flow from one phase (1-2) to the next (1-3) in the direction of rotation of the motor at the phase switch, thereby forcing the unaffected one (2) of said coils by the phase switch into a state of high impedance. Advantageously, the decreasing rate of the current (I2) in the coil (2) unaffected by the phase switch can be twice as high as the decreasing rate of the current (I1) in the phase being switched from.
Abstract:
A high side circuit is described which comprises at least one power device (1) having a first non drivable terminal (D) connected to a supply voltage (Vcc), at least one load (2) connected between a second non drivable terminal (S) of the power device (1) and ground, and driving circuitry (10). The driving circuitry (10) comprises suitable dimensioned transistors (M1, M2, M3) which are connected to each other and to a higher voltage (Vboot) than the supply voltage (Vcc) in order to control the turning on and the turning off of the power device (1) and to minimize the potential difference between the second non drivable terminal (S) and a drivable terminal (G) of the power device (1) during the turning off state to avoid the re-turning on of the same power device.