Semiconductor integrated circuit and sensor driving/measuring system
View Patent ↗In a sensor driving/measuring system, specifications required by a sensor which requires a high applied voltage are implemented with const increase suppressed. A semiconductor integrated circuit for use in a sensor driving/measuring system driven by a battery includes: a sensor driver for outputting a given voltage to be applied to a sensor; a measuring circuit for receiving and measuring a voltage obtained, through current-voltage conversion, from a current generated in the sensor; and a booster. The booster boosts a given pre-boost voltage to obtain a boosted voltage and supplies the boosted voltage as a power supply voltage to the sensor driver and the measuring circuit.
1. A semiconductor integrated circuit for use in a sensor driving/measuring system driven by a battery, the semiconductor integrated circuit comprising:
a sensor driver for outputting a given voltage to be applied to a sensor;
a measuring circuit for receiving and measuring a voltage obtained, through current-voltage conversion, from a current generated in the sensor;
a booster for boosting a given pre-boost voltage to obtain a boosted voltage and for supplying the boosted voltage as a power supply voltage to the sensor driver and the measuring circuit; and
a standard voltage circuit for receiving a power supply voltage from the battery and for outputting a constant standard voltage,
wherein the booster uses, as the given pre-boost voltage, the standard voltage output from the standard voltage circuit, and
each of the sensor driver and the measuring circuit uses, as a reference voltage, the standard voltage output from the standard voltage circuit.
2. The semiconductor integrated circuit of claim 1 , further comprising a current-voltage converter for converting a current generated in the sensor into a voltage.
3. The semiconductor integrated circuit of claim 1 , wherein a current flowing from the standard voltage circuit to the booster is limited during a period after the booster starts boosting and before the boosted voltage is stabilized.
4. The semiconductor integrated circuit of claim 1 , further comprising a digital section for processing an output signal from the measuring circuit.
5. The semiconductor integrated circuit of claim 1 , further comprising a power supply detector for monitoring and managing a power supply voltage from the battery.
6. A battery-driven sensor driving/measuring system for driving and measuring a sensor, the system comprising at least one semiconductor integrated circuit, said at least one semiconductor integrated circuit comprising:
a sensor driver for outputting a given voltage to be applied to the sensor;
a measuring circuit for receiving and measuring a voltage obtained, through current-voltage conversion, from a current generated in the sensor;
a booster for boosting a given pre-boost voltage to obtain a boosted voltage and for supplying the boosted voltage as a power supply voltage to the sensor driver and the measuring circuit; and
a standard voltage circuit for receiving a power supply voltage from the battery and for outputting a constant standard voltage,
wherein the booster uses, as the given pre-boost voltage, the standard voltage output from the standard voltage circuit, and
each of the sensor driver and the measuring circuit uses, as a reference voltage, the standard voltage output from the standard voltage circuit.