Semiconductor device with multiple power sources
View Patent ↗Well bias voltages are generated in accordance with a logic power supply voltage and a memory power supply voltage. The transistor included in a control circuit in a memory core is constituted of a logic transistor manufactured through the same manufacturing steps as those for the transistors of a logic formed on the same semiconductor substrate. Well bias voltages (VBB, VPP) are applied to a back gate of this logic transistor. A memory integrated with a logic on a common semiconductor substrate is provided which allows a transistor of a control circuit therein to be manufactured through the same manufacturing process as that of the logic and allows reduction of current consumption.
1. A semiconductor device comprising:
first internal voltage generation circuitry for generating a voltage internal with respect to said semiconductor device in accordance with a first power supply voltage external with respect to said semiconductor device,
second internal voltage generation circuitry for generating said internal voltage in accordance with a second power supply voltage external with respect to said semiconductor device, said first and second power supply voltages being supplied to said semiconductor device independently and individually upon operation of said semiconductor device. through different paths, and said internal voltage being different in a voltage level from said first and second power supply voltages,
a power on detection circuit for detecting power on of said first power supply voltage, and generating a power on detection signal in accordance with a detection result; and
a voltage holding circuit receiving said second power supply voltage as one operating power supply voltage, for setting said internal voltage at a level of said second power supply voltage in response to the power on detection signal from said power on detection circuit.
2. The semiconductor device according to claim 1 , wherein
when said power on detection signal is activated, said second internal voltage generation circuitry is allowed to perform an operation for generating said internal voltage.
3. A semiconductor device comprising:
first internal voltage generation circuitry for generating a voltage internal with respect to said semiconductor device in accordance with a first power supply voltage external with respect to said semiconductor device,
second internal voltage generation circuitry for generating said internal voltage in accordance with a second power supply voltage external with respect to said semiconductor device, said first and second power supply voltages being supplied to said semiconductor device independently and individually upon operation of said semiconductor device, through different paths, and said internal voltage being different in a voltage level from said first and second power supply voltages,
a first power on detection circuit for detecting power on of said first power supply voltage, and generating a first power on detection signal in accordance with a detection result;
a second power on detection circuit for detecting power on of said second power supply voltage, and generating a second power on detection signal in accordance with a detection result;
a first voltage setting circuit receiving said first power supply voltage as an operating power supply voltage, for setting said internal voltage at a level of said first power supply voltage in response to the second power on detection signal from said second power on detection circuit; and
a second voltage setting circuit receiving said second power supply voltage as an operating power supply voltage, for setting said internal voltage at a level of said second power supply voltage in response to the second power on detection signal from said second power on detection circuit.
4. The semiconductor device according to claim 3 , wherein when said first power on detection signal is activated, said second internal voltage generation circuit is allowed to perform an operation for generating said internal voltage.
5. A semiconductor device comprising:
first internal voltage generation circuitry for generating a voltage internal with respect to said semiconductor device in accordance with a first power supply voltage external with respect to said semiconductor device,
second internal voltage generation circuitry for generating said internal voltage in accordance with a second power supply voltage external with respect to said semiconductor device, said first and second power supply voltages being supplied to said semiconductor device independently and individually upon operation of said semiconductor device, through different paths, and said internal voltage being different in a voltage level from said first and second power supply voltages,
a first voltage setting circuit for setting said internal voltage at a voltage level corresponding to a level of said first power supply voltage in response to power on of said first power supply voltage; and
a second voltage setting circuit for setting said internal voltage at a voltage level corresponding to a level of said second power supply voltage in response to power on of said second power supply voltage.