Semiconductor device and semiconductor system
AssigneeRenesas Electronics Corporation
InventorKazuaki Gemma
Life of this patent
Estimating the term…
Abstract
A semiconductor device selects one start sequence of the normal start and the low-power-consumption start based on the determination result of the determination circuit. According to the configuration, the operation in the start sequence from the power supply input to the processor operation start can be selected from the operation in which the instantaneous current is suppressed and the high-speed operation based on the supplied power supply.
Claims10
A semiconductor device comprising:
- an external terminal;
- a determination circuit configured to determine a voltage of the external terminal;
- a power supply control circuit;
- a clock control circuit;
- a CPU;
- and
- a non-volatile memory,
- wherein the semiconductor device selects one of start sequences of normal start and low-power-consumption start based on a determination result of the determination circuit,
- wherein the start sequence of the low-power-consumption start takes a longer period of time to complete than the start sequence in the normal start,
- wherein the start sequence includes a power supply control, a clock control, and a reset control,
- wherein after the start sequence, the CPU executes instructions stored in the non-volatile memory,
- wherein the semiconductor device further comprises a substrate bias control circuit configured to generate a substrate bias voltage and changing a substrate bias voltage,
- wherein, when the low-power-consumption start is selected, the substrate bias control circuit generates the substrate bias voltage between the power supply control and the clocking control, and changes the substrate bias voltage after the CPU executes instructions stored in the non-volatile memory, and
- wherein, when the low-power-consumption start is selected, internal power supply to the CPU and the clock control circuit is stopped.
A semiconductor system comprising:
- a semiconductor device including;
- an external terminal;
- a determination circuit for determining a voltage of the external terminal;
- a power supply control circuit;
- a clock control circuit;
- a CPU;
- a non-volatile memory a first power supply device;
- a second power supply device having a current supply capability smaller than a current supply capability of the first power supply device;
- and
- a supply circuit configured to select one of the first power supply device and the second power supply device as a power supply of the semiconductor device, and supplying a high level or low level voltage signal to the external terminal in conjunction with selection of one of the first power supply device and the second power supply device,
- wherein the semiconductor device selects one of start sequences of normal start and low power consumption start based on a determination result of the determination circuit,
- wherein the circuit includes a first switch and a second switch,
- wherein in response to the first switch selecting the first power supply device, the second switch supplies a high-level voltage signal to the external terminal, and
- wherein in response to the first switch selecting the second power supply device, the second switch supplies a low-level voltage signal to the external terminal.
A semiconductor device including:
- a fuse circuit;
- a power supply control circuit;
- a clock control circuit;
- a CPU;
- and
- a nonvolatile memory,
- wherein the fuse circuit selects one of a normal start and a low-power-consumption start based on status signals of the fuse circuit,
- wherein the normal start and the low-power-consumption start each includes a start sequence including a power supply control, a clock control, and a reset control,
- wherein when the normal start is selected, the power supply control, the clock control, and the reset control are operated in parallel, and
- wherein when the low-power-consumption start is selected, the power supply control, the clock control, and the reset control are operated sequentially such that the low-power-consumption start takes a longer period of time to complete than the normal start.
A semiconductor system comprising:
- a semiconductor device including;
- an external terminal;
- a determination circuit for determining a voltage of the external terminal;
- a power supply control circuit;
- a clock control circuit;
- a CPU;
- a non-volatile memory;
- a first power supply device;
- a second power supply device having a current supply capability smaller than a current supply capability of the first power supply device;
- and
- a supply circuit configured to select one of the first power supply device and the second power supply device as a power supply of the semiconductor device, and supplying a high level or low level voltage signal to the external terminal in conjunction with selection of one of the first power supply device and the second power supply device,
- wherein the semiconductor device selects one of start sequences of normal start and low power consumption start based on a determination result of the determination circuit,
- wherein the circuit includes a switch control circuit and a switch,
- wherein in response to the switch control circuit selects the first power supply device, the switch control circuit supplies a high-level voltage signal to the external terminal, and the switch control circuit controls the switch to connect the first power supply device to a power supply of the semiconductor device, and
- wherein in response to the switch control circuit selects the second power supply device, the switch control circuit supplies a low-level voltage signal to the external terminal, and the switch control circuit controls the switch to connect the second power supply device to a power supply of the semiconductor device.
A semiconductor system comprising:
- a semiconductor device including;
- an external terminal;
- a determination circuit for determining a voltage of the external terminal;
- a power supply control circuit;
- a clock control circuit;
- a CPU;
- a non-volatile memory;
- a first power supply device;
- a second power supply device having a current supply capability smaller than a current supply capability of the first power supply device;
- and
- a supply circuit configured to select one of the first power supply device and the second power supply device as a power supply of the semiconductor device, and supplying a high level or low level voltage signal to the external terminal in conjunction with selection of one of the first power supply device and the second power supply device,
- wherein the semiconductor device selects one of start sequences of normal start and low power consumption start based on a determination result of the determination circuit,
- wherein the circuit includes a detection circuit for detecting a voltage of a power supply generated by the first power supply device,
- wherein, when the first power supply device generates a power source, the detection circuit supplies a power source generated by the first power supply device to the semiconductor device and supplies a high-level voltage signal to the external terminal, and
- wherein, when the first power supply device does not generate a power source, the detection circuit supplies a power source generated by the second power supply device to the semiconductor device and supplies a low-level voltage signal to the external terminal.
Dependencies are inferred from the claim text.