Reference voltage circuit and electronic device
View Patent ↗In order to realize a reference voltage circuit that operates with lower current consumption while maintaining an operation at lower voltage without causing deterioration of a power supply rejection ratio, provided is a reference voltage circuit in which a depletion transistor of an ED type reference voltage circuit is constituted of a plurality of depletion transistors connected in series, and in which a gate terminal of a cascode depletion transistor is connected to a connection point between the depletion transistors of the ED type reference voltage circuit.
1. A reference voltage circuit, comprising:
an enhancement depletion (ED) type reference voltage circuit comprising:
an N-channel depletion type metal oxide semiconductor (MOS) transistor comprising:
a first N-channel depletion type MOS transistor having a source and a gate connected to an output terminal; and
a second N-channel depletion type MOS transistor having a gate connected to the output terminal, and a source connected to a drain of the first N-channel depletion type MOS transistor, and
an N-channel enhancement type MOS transistor comprising a drain and a gate connected to the output terminal, and a source connected to a ground (GND) terminal, and
a cascode circuit disposed between a power supply terminal and the ED type reference voltage circuit,
wherein the N-channel depletion type MOS transistor comprises a plurality of N-channel depletion type MOS transistors connected in series, and
wherein the cascode circuit comprises an N-channel depletion type MOS transistor comprising a third N-channel depletion type MOS transistor having a drain connected to the power supply terminal, and a gate connected to the drain of the first N-channel depletion type MOS transistor and the source of the second N-channel depletion type MOS transistor.
2. A reference voltage circuit according to claim 1 , wherein at least one of the first N-channel depletion type MOS transistor and the second N-channel depletion type MOS transistor comprises a plurality of N-channel depletion type MOS transistors.
3. An electronic device, comprising the reference voltage circuit according to claim 1 .
4. A reference voltage circuit, comprising:
n ED type reference voltage circuits, where n is an integer of 2 or more, each comprising:
an N-channel depletion type MOS transistor comprising:
a first N-channel depletion type MOS transistor having a source and a gate connected to an output terminal; and
a second N-channel depletion type MOS transistor having a gate connected to the output terminal, and a source connected to a drain of the first N-channel depletion type MOS transistor; and
an N-channel enhancement type MOS transistor having a drain and a gate connected to the output terminal, and a source connected to a GND terminal,
n cascode circuits each disposed between a power supply terminal and each of the n ED type reference voltage circuits,
wherein the N-channel depletion type MOS transistor comprises a plurality of N-channel depletion type MOS transistors connected in series,
wherein each of the n cascode circuits comprises an N-channel depletion type MOS transistor,
wherein the N-channel depletion type MOS transistor of an m-th cascode circuit, where m is an integer satisfying 0<m<n, has a gate connected to any one of connection points between the plurality of N-channel depletion type MOS transistors connected in series of an (m+1)-th ED type reference voltage circuit, and
wherein the N-channel depletion type MOS transistor of an n-th cascode circuit has a gate connected to any one of connection points between the plurality of N-channel depletion type MOS transistors connected in series of a first ED type reference voltage circuit,
wherein the N-channel depletion type MOS transistor of each of the n cascade circuits comprises a third N-channel depletion type MOS transistor having a drain connected to the power supply terminal, and a gate connected to the drain of the first N-channel depletion type MOS transistor and the source of the second N-channel depletion type MOS transistor.
5. A reference voltage circuit according to claim 4 , wherein at least one of the first N-channel depletion type MOS transistor and the second N-channel depletion type MOS transistor comprises a plurality of N-channel depletion type MOS transistors.
6. An electronic device, comprising the reference voltage circuit according to claim 4 .