AC-TO-DC CHARGE PUMP HAVING A CHARGE PUMP AND COMPLIMENTARY CHARGE PUMP

• US 20170324349A1
• Filed: 07/24/2017
• Published: 11/09/2017
• Est. Priority Date: 08/14/2011
• Status: Active Grant

• Current Assignee: Rfmicron, Inc.
• Original Assignee: Rfmicron, Inc.
• Inventors: Paulos, John J., Rokhsaz, Shahriar
• Granted Patent: US 10,560,034 B2
• Time in Patent Office: Days
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps
• CPC Class Codes: H02M 7/103 Containing passive elements (capacitively coupled) which are ordered in cascade on one source

Abstract

An improved AC-to-DC charge pump for use, for example, in voltage generation circuits. In one embodiment, two 2-diode charge pumps are coupled in back-to-back configuration, and adapted to develop a substantially stable voltage on a mid-level rail. In one other embodiment, two 3-diode charge pumps are coupled in back-to-back configuration, and adapted also to develop a substantially stable voltage on a mid-level rail. In one preferred embodiment, all diodes are implemented as current-source-biased MOSFETs.

Claims

1. An AC-to-DC charge pump comprising:

a charge pump operable to convert an AC (alternating current) input voltage into a DC (direct current) voltage; and

a complimentary charge pump operable to convert the AC voltage into a complimentary DC voltage, wherein magnitude of the DC voltage is substantially equal to magnitude of the complimentary DC voltage and wherein the charge pump is coupled to the complimentary charge pump to add the DC voltage and the complimentary DC voltages to produce an output voltage, which has a middle rail that is coupled to a negative leg (V_INN) of the AC input voltage.

2. The charge pump of claim 1 wherein the charge pump circuit comprises:

an input capacitor;

a first diode circuit;

a second diode circuit; and

an output capacitor, wherein a first node of the input capacitor is coupled to a positive leg of the AC input voltage (V_INP), wherein a second node of the input capacitor is coupled to a flying node, wherein a cathode of the first diode circuit is coupled to the flying node and an anode of the first diode circuit is coupled to the middle rail, wherein an anode of the second diode circuit is coupled to the flying node and a cathode of the second diode circuit is coupled to an output node, and wherein a first node of the output capacitor is coupled to the output node and a second node of the output capacitor is coupled to the middle rail.

3. The charge pump of claim 2 wherein the first diode circuit comprises a current-source-biased N-channel MOSFET diode.

4. The charge pump of claim 2 wherein the second diode circuit comprises a current-source-biased P-channel MOSFET diode.

5. The charge pump of claim 1 wherein the complimentary charge pump comprises:

an input capacitor;

a first diode circuit;

a second diode circuit; and

an output capacitor, wherein a first node of the input capacitor is coupled to a positive leg of the AC input voltage (V_INP), wherein a second node of the input capacitor is coupled to a flying node, wherein an anode of the first diode circuit is coupled to the flying node and a cathode of the first diode circuit is coupled to the middle rail, wherein a cathode of the second diode circuit is coupled to the flying node and an anode of the second diode circuit is coupled to an output node, and wherein a first node of the output capacitor is coupled to the output node and a second node of the output capacitor is coupled to the middle rail.

6. The charge pump of claim 5 further comprises:

the second diode circuit including a current-source-biased N-channel MOSFET diode; and

the first diode circuit including current-source-biased P-channel MOSFET diode.

7. An integrated system comprising:

an antenna;

a tank circuit coupled to the antenna;

an AC-to-DC charge pump circuit coupled to the tank circuit, wherein the charge pump circuit includes;

a charge pump operable to convert an AC (alternating current) input voltage received via the antenna into a DC (direct current) voltage; and

a complimentary charge pump operable to convert the AC voltage into a complimentary DC voltage, wherein magnitude of the DC voltage is substantially equal to magnitude of the complimentary DC voltage and wherein the charge pump is coupled to the complimentary charge pump to add the DC voltage and the complimentary DC voltages to produce an output voltage, which has a middle rail that is coupled to a negative leg (V_INN) of the AC input voltage.

8. The integrated system of claim 7, wherein the charge pump circuit comprises:

an input capacitor;

a first diode circuit;

a second diode circuit; and

an output capacitor, wherein a first node of the input capacitor is coupled to a positive leg of the AC input voltage (V_INP), wherein a second node of the input capacitor is coupled to a flying node, wherein a cathode of the first diode circuit is coupled to the flying node and an anode of the first diode circuit is coupled to the middle rail, wherein an anode of the second diode circuit is coupled to the flying node and a cathode of the second diode circuit is coupled to an output node, and wherein a first node of the output capacitor is coupled to the output node and a second node of the output capacitor is coupled to the middle rail.

9. The integrated system of claim 8 further comprises:

the first diode circuit including a current-source-biased N-channel MOSFET diode; and

the second diode circuit including a current-source-biased P-channel MOSFET diode.

10. The integrated system of claim 8, wherein the complimentary charge pump comprises:

an input capacitor;

a first diode circuit;

a second diode circuit; and

an output capacitor, wherein a first node of the input capacitor is coupled to a positive leg of the AC input voltage (V_INP), wherein a second node of the input capacitor is coupled to a flying node, wherein an anode of the first diode circuit is coupled to the flying node and a cathode of the first diode circuit is coupled to the middle rail, wherein a cathode of the second diode circuit is coupled to the flying node and an anode of the second diode circuit is coupled to an output node, and wherein a first node of the output capacitor is coupled to the output node and a second node of the output capacitor is coupled to the middle rail.

11. The integrated system of claim 10 further comprises:

the first diode circuit including a current-source-biased P-channel MOSFET diode; and

the second diode circuit including a current-source-biased N-channel MOSFET diode.

12. The integrated system of claim 7, wherein the charge pump circuit comprises:

a flying node capacitor;

a fixed node capacitor;

a first diode circuit;

a second diode circuit;

a third diode circuit; and

an output capacitor, wherein a first node of the flying node capacitor is coupled to a positive leg of the AC input voltage (V_INP) and a second node of the flying node capacitor is coupled to a flying node, wherein an anode of the first diode circuit is coupled to the V_INP and a cathode of the first diode circuit is coupled to a bias node, wherein an anode of the second diode circuit is coupled to the bias node and a cathode of the second diode circuit is coupled to the flying node, wherein an anode of the third diode circuit is coupled to the flying node and a cathode of the third diode circuit is coupled to an output node, and wherein a first node of the output capacitor is coupled to the output node and a second node of the output capacitor is coupled to the middle rail.

13. The integrated system of claim 12 further comprises:

each of the first and third diode circuits includes a current-source-biased P-channel MOSFET diode; and

the second diode circuit includes a current-source-biased N-channel MOSFET diode.