Power management controller for drivers
View Patent ↗A driver controller comprising a state machine for controlling transitions between a plurality of states. An output switch for providing a low impedance path to ground during transition periods. An output stage for decoupling output signal from driver amplifier during the transition periods.
1. A driver controller comprising:
a state machine for controlling transitions between a plurality of states;
an output switch coupled to the state machine for providing a low impedance path to ground during transition periods;
an output stage coupled to the state machine for controlling signal processing during the transition periods;
an amplifier for amplifying an input signal; and
a reference current generator coupled to the amplifier and the output stage for providing a constant current to the amplifier and an adjustable current to an output stage controller.
2. The driver controller of claim 1 wherein the state machine comprises a port controller for receiving a plurality of state variables and determining state transitions based on the state variables.
3. The driver controller of claim 1 wherein the state machine comprises a port controller for receiving external mute state data, digital to analog converter state data, high definition audio interface control data, and personal computer beep data and determining state transitions between a reset state, a mute state and an enabled state based on the state variables.
4. The driver controller of claim 1 wherein the output stage controller is coupled to the output stage and the state machine, and the output stage controller is configured to receive control data from the state machine and to provide status data to the state machine.
5. The driver controller of claim 1 further comprising a charge pump coupled to the output stage controller and the output stage, the charge pump for providing a negative voltage to the output stage in response to control data received from the output stage controller.
6. The driver controller of claim 1 further comprising:
an amplifier for amplifying an input signal; and
a reference current generator coupled to the amplifier and the output stage for providing current to the amplifier and the output stage controller.
7. The driver controller of claim 1 further comprising:
a clock coupled to the state machine; and
power on reset circuitry coupled to the state machine, wherein the clock and the power on reset circuitry are for controlling power up of the state machine.
8. The driver controller of claim 1 wherein the state machine comprises a reset state that includes a transition to a reset to mute conversion state.
9. The driver controller of claim 1 wherein the state machine comprises a reset to mute conversion state that includes a transition to a mute state.
10. The driver controller of claim 1 wherein the state machine comprises a mute state that includes a transition to an enabled state and a mute to reset conversion state.
11. The driver controller of claim 1 wherein the state machine comprises an enabled state that includes a transition to a mute state.
12. A driver controller comprising:
a state machine for controlling transitions between a plurality of states, the state machine further comprising:
a port controller for receiving external mute state data, digital to analog converter state data, high definition audio interface control data, and personal computer beep data and determining state transitions between a reset state, a mute state and an enabled state based on the state variables;
the reset state includes a transition to a reset to mute conversion state;
the reset to mute conversion state includes a transition to the mute state;
the mute state includes a transition to the enabled state and a mute to reset conversion state;
the enabled state includes a transition to the mute state; and
the mute to reset conversion state includes a transition to the reset state;
an output switch coupled to the state machine for providing a low impedance path to ground during transition periods;
an output stage coupled to the state machine for controlling signal processing during the transition periods;
an output stage controller coupled to the output stage and the state machine, the output stage controller for receiving control data from the state machine and providing status data to the state machine;
a charge pump coupled to the output stage controller and the output stage, the charge pump for providing a negative voltage to the output stage in response to control data received from the output stage controller;
an amplifier for amplifying an input signal;
a reference current generator coupled to the amplifier and the output stage for providing a constant current to the amplifier and an adjustable current the output stage controller;
a clock coupled to the state machine; and
power on reset circuitry coupled to the state machine, wherein the clock and the power on reset circuitry are for controlling power up of the state machine.
13. A driver controller comprising:
a state machine configured to control transitions between a plurality of states, wherein the state machine comprises a port controller configured to receive external mute state data, digital to analog converter state data, high definition audio interface control data, and personal computer beep data and to determine state transitions between a reset state, a mute state and an enabled state based on the state variables;
an output switch coupled to the state machine and configured to provide a low impedance path to ground during transition periods; and
an output stage coupled to the state machine and configured to control signal processing during the transition periods.
14. The driver controller of claim 13 further comprising an output stage controller coupled to the output stage and the state machine and configured to receive control data from the state machine and to provide status data to the state machine.
15. The driver controller of claim 13 further comprising a charge pump coupled to the output stage controller and the output stage, the charge pump is configured to provide a negative voltage to the output stage in response to control data received from an output stage controller.
16. The driver controller of claim 13 further comprising:
an amplifier configured to amplify an input signal; and
a reference current generator coupled to the amplifier and an output stage and configured to provide current to the amplifier and an output stage controller.
17. The driver controller of claim 13 further comprising an amplifier for amplifying an input signal.
18. The driver controller of claim 17 further comprising a reference current generator coupled to the amplifier and the output stage for providing a constant current to the amplifier and an adjustable current to an output stage controller.
19. The driver controller of claim 13 further comprising a clock coupled to the state machine.
20. The driver controller of claim 19 further comprising power on reset circuitry coupled to the state machine, wherein the clock and the power on reset circuitry are for controlling power up of the state machine.