Low leakage level shifter

1 . A level shifter comprising:

an input connection configured to receive an input signal;

an output connection configured to provide an output signal;

a voltage rail configured to provide a rail voltage;

at least two diodes including a first diode and a second diode connected in series between the voltage rail and the input connection;

at least three switches including a first switch, a second switch, and a third switch, the first switch being coupled between the voltage rail and an output of the first diode, the second switch coupled between the voltage rail and an output of the second diode, and the third switch coupled between the voltage rail and the input connection; and

a capacitor coupled between the output of the second diode and ground.

2 . The level shifter of claim 1 wherein the at least two diodes are transistors having their respective sources shorted to their respective gates.

3 . The level shifter of claim 1 further comprising a first inverter coupled to the input connection.

4 . The level shifter of claim 3 wherein an output of the first inverter is coupled to a gate of each of the at least three switches.

5 . The level shifter of claim 4 further comprising a second inverter coupled to the output of the first inverter.

6 . The level shifter of claim 5 wherein the at least two diodes further include one or more additional diodes, each additional diode connected in series between the output of the first diode and the input of the second diode.

7 . The level shifter of claim 6 wherein the at least three switches include one or more additional switches, each respective additional switch coupled between the voltage rail and an output of a respective additional diode of the one or more additional diodes.

8 . The level shifter of claim 7 further comprising a plurality of additional capacitors, each respective additional capacitor coupled between an output of a respective additional diode and ground.

9 . The level shifter of claim 7 wherein the output of the first inverter is coupled to the gates of the one or more additional switches.

10 . The level shifter of claim 1 wherein the input connection comprises at least two transistors coupled in series between the output of the second diode and ground.

11 . The level shifter of claim 1 wherein the level shifter has at least two states including a first state corresponding to providing the output signal at the output connection and a second state corresponding to not providing the output signal at the output connection.

12 . A level shifter comprising:

an input connection;

an output connection;

a first node configured to provide a voltage;

a plurality of current-blocking circuit elements configured to allow current to pass from the first node to the input connection but not from the input connection to the first node, the plurality of current-blocking circuit elements being coupled in series with respect to each other between the input connection and the first node;

a plurality of switches, each switch of the plurality of switches having a respective first terminal directly coupled to the first node, and each current-blocking circuit element of the plurality of current-blocking circuit elements having at least one terminal coupled directly to a respective second terminal of one respective switch of the plurality of switches; and

a capacitor coupled to the plurality of current-blocking circuit elements and the input connection.

13 . The level shifter of claim 12 wherein the plurality of current-blocking circuit elements are diodes.

14 . The level shifter of claim 12 wherein the plurality of current blocking circuit elements are transistors configured to operate as diodes.

15 . The level shifter of claim 12 wherein the plurality of switches includes:

a first switch coupled to the first node and to a first current-blocking circuit element of the plurality of current-blocking circuit elements at a node other than the first node;

a second switch coupled to the first node and to a second current-blocking circuit element of the plurality of current-blocking circuit elements, the second current-blocking circuit element being coupled to the first current-blocking circuit element; and

a third switch coupled to the first node and to a third current-blocking circuit element of the plurality of current-blocking circuit elements, the third current-blocking circuit element being coupled to the second current-blocking circuit element.

16 . The level shifter of claim 12 wherein the level shifter includes a plurality of capacitors, the plurality of capacitors including the capacitor, wherein each respective switch of the plurality of switches is coupled to a respective capacitor of the plurality of capacitors.

17 . The level shifter of claim 12 further comprising:

a first inverter coupled to the input connection; and

a second inverter coupled between the first inverter and the output connection.

18 . The level shifter of claim 17 wherein the first inverter is coupled to a respective control input of each switch of the plurality of switches, the respective control input of each respective switch being configured to control a respective state of each respective switch of the plurality of switches.

19 . A level shifter comprising:

an input connection;

and output connection;

a first inverter having a first inverter input and a first inverter output;

a second inverter having a second inverter input and a second inverter output, the first inverter coupled to the input connection via the first inverter input and coupled to the second inverter input via the first inverter output, the second inverter coupled to the output connection via the second inverter output;

a plurality of diodes coupled between a voltage rail and the input connection;

a capacitor coupled between the input connection and ground; and

a plurality of switching devices coupled to the voltage rail, each respective control input for each respective switching device of the plurality of switching devices being coupled to the first inverter via the first inverter output.