Drive unit for driving voltage-driven element

• US 8,866,515 B2
• Filed: 06/02/2011
• Issued: 10/21/2014
• Est. Priority Date: 06/02/2011
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Wasekura, Masaki
• Primary Examiner(s): Donovan, Lincoln
• Assistant Examiner(s): Almo, Khareem E
• Application Number:
  US13/882,594
• Publication Number:
  US 20130214825A1
• Time in Patent Office: 1,237 Days
• Field of Search: None
• US Class Current: 327/109
• 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: H03K 17/163 Soft switching
• CPC Class Codes: H03K 17/296 Time-programme switches providing a choice of time-intervals for executing more than one switching action and automatically terminating their operation after the programme is completed electronic clocks comprising means to be operated at preselected times or after preselected time-intervals G04G15/00

Abstract

A drive unit comprises a switching circuit and an abnormal signal generating circuit. The switching circuit is configured to be connected to an external time generating circuit, and is configured to switch a driving condition relating to a driving voltage of a voltage-driven element in a transitional period between a driving state and a non-driving state of the voltage-driven element based on a measurement time which is measured by using of the time generating circuit. The abnormal signal generating circuit is configured to generate an abnormal signal when an accurate measurement of the time using the time generating circuit is not executed.

Claims

1. A drive unit for driving a voltage-driven element, the drive unit comprising:

a switching circuit; and

an abnormal signal generating circuit, wherein

the switching circuit is configured to be connected to an external time generating circuit, and is configured to switch a driving condition relating to a driving voltage of the voltage-driven element during a transitional period between a driving state and a non-driving state of the voltage-driven element based on a measurement time which is measured by using the time generating circuit, and

the abnormal signal generating circuit is configured to generate an abnormal signal when an accurate measurement of the time using the time generating circuit is not executed,

the switching circuit is configured to measure the time after the transitional period starts by using the time generating circuit, and is configured to switch the driving condition when the measurement time reaches a first predetermined time,

the switching circuit includes a reference current source and a comparator,

the reference current source is configured to be connected to a capacitor disposed in the time generating circuit, and is configured to provide a reference current to the capacitor after the transitional period starts, and

the comparator is configured to be connected to the capacitor of the time generating circuit, and is configured to determine that the measurement time reached the first predetermined time when a voltage on a connection line which is connected to the capacitor reaches a first threshold voltage.

2. The drive unit according to claim 1, wherein

a magnitude of the reference current of the reference current source is controlled by using a resistive element disposed in the time generating circuit, and

the abnormal signal generating circuit is configured to generate the abnormal signal at least when the magnitude of the reference current of the reference current source is at one of an upper threshold or higher and a lower threshold or lower.

3. The drive unit according to claim 1 wherein

the abnormal signal generating circuit is configured to measure the time after the transitional period starts, and is configured to generate the abnormal signal when the voltage on the connection line which connects the comparator of the switching circuit to the capacitor of the time generating circuit has reached a second threshold voltage at a second predetermined time prior to the first predetermined time.

4. The drive unit according to claim 3, wherein

the first threshold voltage and the second threshold voltage are same value.

5. The drive unit according to claim 1 wherein

the abnormal signal generating circuit is configured to measure the time after the transitional period starts, and is configured to generate the abnormal signal when the driving condition is not switched at a third predetermined time later than the first predetermined time.