Multi-mode low current dual voltage self-regulated LCD pump system
A bias voltage generator circuit may include a mode control circuit, a clock generator circuit coupled with the mode control unit and configured to generate a plurality of clock signals, and a charge pump circuit configured to receive the clock signals. The charge pump circuit may be coupled with the mode control circuit and operable to output selectable output voltages according to input from the mode control circuit. The output selectable voltages may depend upon the clock signals.
1. A bias voltage generator circuit comprising:
a mode control circuit;
a clock generator circuit coupled with the mode control unit and configured to generate a plurality of clock signals;
a charge pump circuit configured to receive the clock signals, coupled with the mode control circuit, and operable to output selectable output voltages according to input from the mode control circuit, the output selectable voltages depending upon the clock signals; and
a bootstrap circuit coupled between the clock generator circuit and the charge pump circuit.
2. The bias voltage generator circuit according to claim 1 , wherein the mode control circuit is configured to select between a plurality of operating modes defining output of the charge pump circuit.
3. The bias voltage generator circuit according to claim 2 , wherein a first operating mode is configured to provide for a bias voltage with a first current for an LCD and a second operating mode is configured to provide the bias voltage with a second current for the LCD.
4. The bias voltage generator circuit according to claim 1 , wherein the clock signals include non-overlapping pulses of a base signal and a plurality of phased signals, the phased signals selected according to specified output of the charge pump circuit.
5. The bias voltage generator circuit according to claim 1 , wherein the clock signals include non-overlapping pulses of a base signal and one or more phased signals, and the charge pump circuit is configured to output bias voltages based upon the presence of alternating ones of the phased signals.
6. The bias voltage generator circuit according to claim 1 , wherein:
the clock signals include non-overlapping pulses of a base signal and one or more phased signals;
the charge pump circuit is configured to output a voltage based on a number of different phased signals.
7. The bias voltage generator circuit according to claim 1 , wherein:
the clock signals include non-overlapping pulses of a base signal and one or more phased signals;
the charge pump circuit is configured to output a bias voltage with a current, the current based upon a number of different phased signals.
8. A bias voltage generator circuit comprising:
a mode control circuit;
a clock generator circuit coupled with the mode control unit and configured to generate a plurality of clock signals; and
a charge pump circuit configured to receive the clock signals, coupled with the mode control circuit, and operable to output selectable output voltages according to input from the mode control circuit, the output selectable voltages depending upon the clock signals;
wherein a first operating mode is configured to provide for a bias voltage for a 3V LCD and a second operating mode is configured to provide for a bias voltage for a 5V LCD.
9. A bias voltage generator circuit comprising:
a mode control circuit;
a clock generator circuit coupled with the mode control unit and configured to generate a plurality of clock signals; and
a charge pump circuit configured to receive the clock signals, coupled with the mode control circuit, and operable to output selectable output voltages according to input from the mode control circuit, the output selectable voltages depending upon the clock signals;
wherein:
the clock signals include non-overlapping pulses of a base signal and one or more phased signals;
the charge pump circuit is configured to output a first voltage based upon the presence of a first number of different phased signals;
the charge pump circuit is configured to output a second voltage based upon the presence of a second number of different phased signals;
the second voltage is higher than the first voltage; and
the second number of different phased signals is greater than the first number of different phased signals.
10. A microcontroller comprising:
a bias voltage generator circuit; and
an output routing circuit, the output routing circuit configured to route output from the bias voltage generator circuit to a display;
wherein the bias voltage generator circuit comprises:
a mode control circuit;
a clock generator circuit coupled with the mode control unit and configured to generate a plurality of clock signals;
a charge pump circuit configured to receive the clock signals, coupled with the mode control circuit, and operable to output selectable output voltages according to input from the mode control circuit, the output selectable voltages depending upon the clock signals; and
a bootstrap circuit coupled between the clock generator circuit and the charge pump circuit.
11. The microcontroller according to claim 10 , wherein the mode control circuit is configured to select between a plurality of operating modes defining output of the charge pump circuit.
12. The microcontroller according to claim 11 , wherein a first operating mode is configured to provide for a bias voltage with a first current for an LCD and a second operating mode is configured to provide the bias voltage with a second current for the LCD.
13. The microcontroller according to claim 10 , wherein the clock signals include non-overlapping pulses of a base signal and a plurality of phased signals, the phased signals selected according to specified output of the charge pump circuit.
14. The microcontroller according to claim 10 , wherein the clock signals include non-overlapping pulses of a base signal and one or more phased signals, and the charge pump circuit is configured to output bias voltages based upon the presence of alternating ones of the phased signals.
15. The microcontroller according to claim 10 , wherein:
the clock signals include non-overlapping pulses of a base signal and one or more phased signals;
the charge pump circuit is configured to output a voltage based on a number of different phased signals.
16. The microcontroller according to claim 10 , wherein:
the clock signals include non-overlapping pulses of a base signal and one or more phased signals;
the charge pump circuit is configured to output a bias voltage with a current, the current based upon a number of different phased signals.
17. A microcontroller comprising:
a bias voltage generator circuit; and
an output routing circuit, the output routing circuit configured to route output from the bias voltage generator circuit to a display;
wherein the bias voltage generator circuit comprises:
a mode control circuit;
a clock generator circuit coupled with the mode control unit and configured to generate a plurality of clock signals;
a charge pump circuit configured to receive the clock signals, coupled with the mode control circuit, and operable to output selectable output voltages according to input from the mode control circuit, the output selectable voltages depending upon the clock signals;
wherein a first operating mode is configured to provide for a bias voltage for a 3V LCD and a second operating mode is configured to provide for a bias voltage for a 5V LCD.
18. A microcontroller comprising:
a bias voltage generator circuit; and
an output routing circuit, the output routing circuit configured to route output from the bias voltage generator circuit to a display;
wherein the bias voltage generator circuit comprises:
a mode control circuit;
a clock generator circuit coupled with the mode control unit and configured to generate a plurality of clock signals;
a charge pump circuit configured to receive the clock signals, coupled with the mode control circuit, and operable to output selectable output voltages according to input from the mode control circuit, the output selectable voltages depending upon the clock signals;
wherein:
the clock signals include non-overlapping pulses of a base signal and one or more phased signals;
the charge pump circuit is configured to output a first voltage based upon the presence of a first number of different phased signals;
the charge pump circuit is configured to output a second voltage based upon the presence of a second number of different phased signals;
the second voltage is higher than the first voltage; and
the second number of different phased signals is greater than the first number of different phased signals.