Inverter

• US 6,850,097 B2
• Filed: 10/09/2003
• Issued: 02/01/2005
• Est. Priority Date: 12/17/2001
• Status: Expired due to Fees

• Current Assignee: CoolIT Systems Inc.
• Original Assignee: CoolIT Systems Inc.
• Inventors: Scott, Robert John Charles
• Primary Examiner(s): ZWEIZIG, JEFFERY SHAWN
• Application Number:
  US10/681,225
• Publication Number:
  US 20040120170A1
• Time in Patent Office: 481 Days
• Field of Search: 327/58, 327/60, 327/62, 327/72, 327/74, 327/78, 327/126, 327/127, 327/131
• US Class Current: 327/58
• CPC Class Codes: H02M 1/08 Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
• CPC Class Codes: H02M 1/088 for the simultaneous control of series or parallel connected semiconductor devices
• CPC Class Codes: H02M 1/38 Means for preventing simultaneous conduction of switches
• CPC Class Codes: H02M 7/53871 with automatic control of output voltage or current

Abstract

AC to DC inverters that are formed from electronic switches, such as MOSFETs, that are controlled by gating pulses obtained from comparators. The comparators compare a varying signal against two closely spaced reference voltages so as to provide gating pulses with delays needed to prevent shoot-through in the electronic switches.

Claims

1. An electronic circuit, comprising:

a voltage reference source for providing a first reference voltage and a second reference voltage, the first reference voltage more positive the second reference voltage, the voltage reference source including a voltage divider connected between a first DC input terminal and a second DC input terminal, the voltage divider providing the first reference voltage and the second reference voltage, the voltage divider including a resistive voltage ladder providing a DC-offset reference voltage between the first reference voltage the second reference voltage;

a signal generator for generating a reference signal that varies between a maximum voltage that is more positive than the first reference voltage and a minimum voltage that is less positive than the second reference voltage;

a voltage follower connected between the resistive voltage ladder and the signal generator so as to provide the DC-offset reference voltage to the signal generator;

a first comparator connected to the signal generator and the voltage reference source so as to compare the reference signal to the first reference voltage and provide as an output a first series of output pulses each of which lasts during a discrete interval during which the reference signal is more positive than the first reference voltage; and

a second comparator connected to the signal generator and the voltage reference source so as to compare the reference signal to the second reference voltage and provide as an output a second series of output pulses each of which lasts during a discrete interval during which the reference signal is less positive than the second reference voltage.

2. The electronic circuit as defined in claim 1, wherein the output pulses are positive going pulses.

3. An electronic circuit, comprising:

a voltage reference source for providing a first reference voltage and a second reference voltage, the first reference voltage more positive than the second reference voltage, the voltage reference source including a voltage divider connected between a first DC input terminal second DC input terminal the voltage divider providing the first reference voltage and the second reference voltage, the voltage divider including a resistive voltage ladder providing a DC-offset reference voltage between the first reference voltage and the second reference voltage;

a signal generator for generating a reference signal that varies between a maximum voltage that is more positive than the first reference voltage and a minimum voltage that is less positive than the second reference voltage;

a voltage follower connected between the resistive voltage ladder and the signal generator so as to provide the DC-offset reference voltage to the signal generator,

a first comparator connected to the signal generator and the voltage reference source so as to compare the reference signal to the first reference voltage and provide as an output a first series of output pulses each of which lasts during a discrete interval during which the reference signal is more positive than the first reference voltage; and

a second comparator connected to the signal generator and the voltage reference source so as to compare the reference signal to the second reference voltage and provide as an output a second series of output pulses each of which lasts during a discrete interval during which the reference signal is more positive than the second reference voltage.

4. The electronic circuit as defined in claim 3, wherein the output pulses are positive going pulses.