A programmable-threshold diode device, comprising a cathode terminal; an anode terminal; a protection device having a protection control input coupled with the anode terminal, such that application at the anode terminal of a voltage level exceeding a protection threshold voltage level permits current to flow through the protection device, the protection threshold voltage level being non-positive; and a low-threshold-voltage diode bank comprising a plurality of parallel paths, each parallel path comprising: a switch of a plurality of switches; and a low-threshold-voltage device of a plurality of low-threshold-voltage devices, each low-threshold-voltage device having a respective threshold voltage that is different from that of at least some others of the plurality of low-threshold-voltage devices, the low-threshold-voltage device coupled between the anode terminal and the switch, and having a diode control input coupled with the anode terminal, such that application at the anode terminal of a voltage level exceeding the respective threshold voltage permits current to flow through the low-threshold-voltage device, wherein closing the switch couples the low-threshold-voltage device to the protection device; wherein the protection device is a depletion mode, metal-oxide semiconductor transistor having a gate, a drain, and a source; the gate of the protection device is the protection control input coupled with the anode terminal; the source of the protection device is coupled to the cathode terminal; and the drain of the protection device is coupled with the plurality of switches; and wherein for each parallel path: the low-threshold-voltage device is a diode-connected, enhancement mode, metal-oxide semiconductor transistor having a gate, a drain, and a source; the gate of the low-threshold-voltage device is the diode control input coupled with the anode terminal; the drain of the low-threshold-voltage device is coupled to the anode terminal; and the source of the low-threshold-voltage device is coupled with the switch. a cathode terminal; an anode terminal; a protection device having a protection control input coupled with the anode terminal, such that application at the anode terminal of a voltage level exceeding a protection threshold voltage level permits current to flow through the protection device, the protection threshold voltage level being non-positive; and a low-threshold-voltage diode bank comprising a plurality of parallel paths, each parallel path comprising: a switch of a plurality of switches; and a low-threshold-voltage device of a plurality of low-threshold-voltage devices, each low-threshold-voltage device having a respective threshold voltage that is different from that of at least some others of the plurality of low-threshold-voltage devices, the low-threshold-voltage device coupled between the anode terminal and the switch, and having a diode control input coupled with the anode terminal, such that application at the anode terminal of a voltage level exceeding the respective threshold voltage permits current to flow through the low-threshold-voltage device, wherein closing the switch couples the low-threshold-voltage device to the protection device; a switch of a plurality of switches; and a low-threshold-voltage device of a plurality of low-threshold-voltage devices, each low-threshold-voltage device having a respective threshold voltage that is different from that of at least some others of the plurality of low-threshold-voltage devices, the low-threshold-voltage device coupled between the anode terminal and the switch, and having a diode control input coupled with the anode terminal, such that application at the anode terminal of a voltage level exceeding the respective threshold voltage permits current to flow through the low-threshold-voltage device, wherein closing the switch couples the low-threshold-voltage device to the protection device; wherein the protection device is a depletion mode, metal-oxide semiconductor transistor having a gate, a drain, and a source; the gate of the protection device is the protection control input coupled with the anode terminal; the source of the protection device is coupled to the cathode terminal; and the drain of the protection device is coupled with the plurality of switches; and wherein for each parallel path: the low-threshold-voltage device is a diode-connected, enhancement mode, metal-oxide semiconductor transistor having a gate, a drain, and a source; the gate of the low-threshold-voltage device is the diode control input coupled with the anode terminal; the drain of the low-threshold-voltage device is coupled to the anode terminal; and the source of the low-threshold-voltage device is coupled with the switch. the low-threshold-voltage device is a diode-connected, enhancement mode, metal-oxide semiconductor transistor having a gate, a drain, and a source; the gate of the low-threshold-voltage device is the diode control input coupled with the anode terminal; the drain of the low-threshold-voltage device is coupled to the anode terminal; and the source of the low-threshold-voltage device is coupled with the switch.