Methods and devices to control PCM switches are disclosed. The described devices include PCM switch drivers and logic and control circuits, all integrated with the PCM and the associated heater on the same chip. Various architectures for the driver are also presented, including architectures implement feedback mechanism to mitigate variations from process, temperature, and supply voltage.

An example apparatus includes: charge injection circuitry having a first terminal, a second terminal, and a control terminal; first inductor-capacitor (LC) circuitry having a first terminal and a second terminal, the first terminal of the first LC circuitry coupled to the first terminal of the charge injection circuitry, the second terminal of the first LC circuitry coupled to the second terminal of the charge injection circuitry; second LC circuitry magnetically coupled to the first LC circuitry; and current sense circuitry having an input terminal coupled to the control terminal of the charge injection circuitry.

An example apparatus includes: charge injection circuitry having a first terminal, a second terminal, and a control terminal; first inductor-capacitor (LC) circuitry having a first terminal and a second terminal, the first terminal of the first LC circuitry coupled to the first terminal of the charge injection circuitry, the second terminal of the first LC circuitry coupled to the second terminal of the charge injection circuitry; second LC circuitry magnetically coupled to the first LC circuitry; and current sense circuitry having an input terminal coupled to the control terminal of the charge injection circuitry.

According to an embodiment, a power supply management circuit of a printer includes a first switch, a second switch, a logic circuit, a power supply management integrated circuit, and a control circuit. When the first switch is switched, the logic circuit closes the second switch, and the power supply management integrated circuit starts sequence control of power supply startup in accordance with the closing. Further, when the first switch is long-pressed, the power supply management integrated circuit starts sequence control of power supply shutdown, and the control circuit causes the logic circuit to output a control signal to open the second switch.

According to an embodiment, a power supply management circuit of a printer includes a first switch, a second switch, a logic circuit, a power supply management integrated circuit, and a control circuit. When the first switch is switched, the logic circuit closes the second switch, and the power supply management integrated circuit starts sequence control of power supply startup in accordance with the closing. Further, when the first switch is long-pressed, the power supply management integrated circuit starts sequence control of power supply shutdown, and the control circuit causes the logic circuit to output a control signal to open the second switch.