<Ul> <Li> Voltage controlled negative resistance (VCNR, short - circuit stable, or "N" type): In this type the current is a single valued, continuous function of the voltage, but the voltage is a multivalued function of the current . In the most common type there is only one negative resistance region, and the graph is a curve shaped generally like the letter "N". As the voltage is increased, the current increases (positive resistance) until it reaches a maximum (i), then decreases in the region of negative resistance to a minimum (i), then increases again . Devices with this type of negative resistance include the tunnel diode, resonant tunneling diode, lambda diode, Gunn diode, and dynatron oscillators . </Li> </Ul> <Li> Voltage controlled negative resistance (VCNR, short - circuit stable, or "N" type): In this type the current is a single valued, continuous function of the voltage, but the voltage is a multivalued function of the current . In the most common type there is only one negative resistance region, and the graph is a curve shaped generally like the letter "N". As the voltage is increased, the current increases (positive resistance) until it reaches a maximum (i), then decreases in the region of negative resistance to a minimum (i), then increases again . Devices with this type of negative resistance include the tunnel diode, resonant tunneling diode, lambda diode, Gunn diode, and dynatron oscillators . </Li> <Ul> <Li> Current controlled negative resistance (CCNR, open - circuit stable, or "S" type): In this type, the dual of the VCNR, the voltage is a single valued function of the current, but the current is a multivalued function of the voltage . In the most common type, with one negative resistance region, the graph is a curve shaped like the letter "S". Devices with this type of negative resistance include the IMPATT diode, UJT, SCRs and other thyristors, electric arc, and gas discharge tubes like thyratron tubes, fluorescent lamps and neon lights . </Li> </Ul> <Li> Current controlled negative resistance (CCNR, open - circuit stable, or "S" type): In this type, the dual of the VCNR, the voltage is a single valued function of the current, but the current is a multivalued function of the voltage . In the most common type, with one negative resistance region, the graph is a curve shaped like the letter "S". Devices with this type of negative resistance include the IMPATT diode, UJT, SCRs and other thyristors, electric arc, and gas discharge tubes like thyratron tubes, fluorescent lamps and neon lights . </Li>

Concept of negative resistance in context with scr
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