Power stealing circuit to charge a capacitor

• US 20020186070A1
• Filed: 06/07/2001
• Published: 12/12/2002
• Est. Priority Date: 06/07/2001
• Status: Abandoned Application

• Current Assignee: EM Design Incorporated
• Original Assignee: EM Design Incorporated
• Inventors: Wall, Bruce Carl, Arachtingi, John William
• Application Number:
  US09/876,537
• Publication Number:
  US 20020186070A1
• Time in Patent Office: Days
• US Class Current: 327/530
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02M 7/217 using semiconductor devices only
• CPC Class Codes: H03K 17/302 in field-effect transistor switches
• CPC Class Codes: H03K 2017/307 circuits simulating a diode, e.g. threshold zero

Abstract

A power stealing circuit to charge a capacitor includes a passive electrical power channel. The passive electrical power channel has an input connected to an input signal and an output designed to be connected to the capacitor. An active electrical power channel is powered by the capacitor. The active electrical power channel has an input connected to the input signal and an output connected to the capacitor.

Claims

1. A power stealing circuit to charge a capacitors comprising:

an operational amplifier having an inverting input connected to an input signal;

a transistor having a gate connected to an output of the operational amplifier, a drain is connected to the inverting input of the operational amplifier and a source is connected to a non-inverting input of the operational amplifier; and

an electrical connector electrically connected to the source of the transistor and designed to be connected to the capacitor.

2. The circuit of claim 1, further including a diode having an anode connected to the inverting input of the operational amplifier and a cathode connected to the non-inverting input of the operational amplifier.

3. The circuit of claim 2, wherein the operational amplifier receives power from the capacitor.

4. The circuit of claim 3, wherein the circuit is implemented on an integrated circuit.

5. The circuit of claim 4, wherein the integrated circuit is a complementary metal oxide integrated circuit.

6. The circuit of claim 3, further including an ESD connected transistor electrically connected in parallel with the diode.

7. The circuit of claim 6, further including a second transistor electrically connected from the inverting input to a ground.

8. The circuit of claim 2, wherein the diode is a poly diode.

9. A power stealing circuit to charge a capacitor, comprising:

a passive electrical power channel having an input connected to an input signal and an output designed to be connected to the capacitor; and

an active electrical power channel powered by the capacitor and having an input connected to the input signal and an output connected to the capacitor.

10. The circuit of claim 9, wherein the passive electrical power channel is a diode.

11. The circuit of claim 9, wherein the active electrical power channel includes an operational amplifier having an inverting input connected to the input signal.

12. The circuit of claim 11, wherein the input signal is an information signal.

13. The circuit of claim 11, wherein the active electrical power channel includes a transistor having a gate connected to an output of the operational amplifier, a source is connected to a non-inverting input of the operational amplifier, a drain is connected to the inverting input of the operational amplifier.

14. The circuit of claim 13, wherein the source is designed to be connected to the capacitor.

16. The circuit of claim 15, further including an electrical connector electrically connected to the source of the transistor and designed to be connected to the capacitor.

17. The circuit of claim 15, wherein the diode is a Poly-diode.

18. The circuit of claim 15, circuit is a complementary metal oxide integrated circuit.

15. A power stealing circuit to charge a capacitor, comprising:

a comparator having a first input connected to an input signal;

a diode having an anode connected to the first input of the comparator and a cathode connected to a second input of the comparator; and

a transistor having a gate connected to an output of the comparator, a drain is connected to the first input of the comparator and a source is connected to the second input of the comparator.