Selectively adjustable voltage detection integrated circuit
AssigneeKabushiki Kaisha Suwa Seikosha
InventorsAsakawa Tatsushi, Morozumi Shinji
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AssigneeKabushiki Kaisha Suwa Seikosha
InventorsAsakawa Tatsushi, Morozumi Shinji
Estimating the term…
A voltage detection integrated circuit including a voltage regulation circuit for controlling the operation thereof is provided. The voltage detection integrated circuit includes a reference voltage circuit for producing a predetermined reference voltage, a voltage converter for converting a detected voltage for measurement and a comparator circuit for comparing the level of the reference voltage to the level of the converted voltage and for producing a comparison signal representative of the difference in voltage levels compared thereby. The voltage regulation circuit is coupled to the comparator circuit and the reference voltage circuit and/or voltage conversion circuit for selectively adjusting the level of the reference voltage produced by the reference voltage circuit and/or the converted voltage produced by the voltage converter, to thereby control the comparison signal produced by the comparator circuit.
In a voltage detection circuit, the improvement comprising a source voltage, a reference voltage circuit means for receiving said source voltage, said reference voltage circuit means including at least first and second pairs of complementary coupled P-channel and N-channel MOS transistors, said P-channel transistor in said first pair being coupled in series with said N-channel transistor in said first pair, said P-channel transistor in said second pair being coupled in series with said N-channel transistor in said second pair, at least one of said transistors in said first pair of complementary coupled P-channel and N-channel transistors having a different threshold voltage than the like polarity transistor in the second pair of complementary coupled P-channel and N-channel transistors, said reference voltage circuit means defining at least a first predetermined voltage having a magnitude that is related to the difference in threshold voltages between said respective like polarity transistors in said first and second pairs, said predetermined voltage being substantially independent of variations in temperature and minor variations in said source voltage, said reference voltage circuit means producing a set reference output voltage at said predetermined voltage in response to said source voltage.
Dependencies are inferred from the claim text.