A selectable threshold reset circuit coupled to a first power supply terminal (V DD) and a second power supply terminal (Vss), comprising: a voltage-divider circuit coupled to the first power supply terminal (V DD) and to the second power supply terminal (Vss), for producing a V SENSE voltage that is a fraction of a voltage at the first power supply terminal; a comparator having a first input terminal coupled to the V SENSE voltage produced by the voltage divider circuit, a second input terminal coupled to a reference voltage (V REF), and an output terminal for outputting a RESET signal when the first power supply terminal (V DD) is at a voltage equal to or less than a reset threshold voltage of the selectable threshold reset circuit; and a switch for controlling the voltage-divider circuit, the switch having a first switch terminal coupled to the voltage-divider circuit, a second switch terminal coupled to the second power supply terminal (Vss), and an input terminal for activating the switch, such that, when the switch is in a first state and the first power supply terminal (V DD) is at a normal power supply voltage level, the RESET signal is outputted at a normal reset threshold voltage, and, when the switch is in a second state and the first power supply terminal (V DD) is at a test mode voltage level that is less than the normal power supply voltage level, the RESET signal is outputted at a test mode reset threshold voltage that is less than the normal reset threshold voltage; characterized by: a pullup resistor coupled between the input terminal of the switch and the first power supply terminal, such that the reset threshold voltage remains at the normal reset threshold voltage in absence of a signal at the input terminal of the switch. a voltage-divider circuit coupled to the first power supply terminal (V DD) and to the second power supply terminal (Vss), for producing a V SENSE voltage that is a fraction of a voltage at the first power supply terminal; a comparator having a first input terminal coupled to the V SENSE voltage produced by the voltage divider circuit, a second input terminal coupled to a reference voltage (V REF), and an output terminal for outputting a RESET signal when the first power supply terminal (V DD) is at a voltage equal to or less than a reset threshold voltage of the selectable threshold reset circuit; and a switch for controlling the voltage-divider circuit, the switch having a first switch terminal coupled to the voltage-divider circuit, a second switch terminal coupled to the second power supply terminal (Vss), and an input terminal for activating the switch, such that, when the switch is in a first state and the first power supply terminal (V DD) is at a normal power supply voltage level, the RESET signal is outputted at a normal reset threshold voltage, and, when the switch is in a second state and the first power supply terminal (V DD) is at a test mode voltage level that is less than the normal power supply voltage level, the RESET signal is outputted at a test mode reset threshold voltage that is less than the normal reset threshold voltage; when the switch is in a first state and the first power supply terminal (V DD) is at a normal power supply voltage level, the RESET signal is outputted at a normal reset threshold voltage, and, when the switch is in a second state and the first power supply terminal (V DD) is at a test mode voltage level that is less than the normal power supply voltage level, the RESET signal is outputted at a test mode reset threshold voltage that is less than the normal reset threshold voltage; characterized by: a pullup resistor coupled between the input terminal of the switch and the first power supply terminal, such that the reset threshold voltage remains at the normal reset threshold voltage in absence of a signal at the input terminal of the switch.