Charge pump power supply circuit

• US 20050270086A1
• Filed: 06/03/2005
• Published: 12/08/2005
• Est. Priority Date: 06/04/2004
• Status: Active Grant

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: Renesas Technology Corporation (Renesas Electronics Corporation)
• Inventors: Sohara, Yasuyuki
• Granted Patent: US 7,208,997 B2
• Time in Patent Office: Days
• US Class Current: 327/536
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps

Abstract

In a basic circuit of a booster circuit, two charging units perform a charging operation and two boosting units perform a boosting operation (discharging operation). One of the charging units is connected to voltage input and the other is connected to voltage output. The charging unit that is connected to the voltage input includes three parallel connected MOS transistors Q11, Q21, and Q13, the other charging unit includes a MOS transistor Q4. One of the boosting units is connected to voltage input and the other is connected to voltage output. The boosting unit that is connected to the voltage input includes three parallel connected MOS transistors Q31, Q32, and Q33, the other boosting unit includes a MOS transistor Q2. Q11 and Q31 are turned ON immediately after start up, then Q12 and Q22 are turned ON operation, and finally Q13 and Q23 are turned ON.

Claims

1. A charge pump power supply circuit comprising:

two charging units that perform an operation of charging a capacitor up to an input voltage, at least one of the two charging units includes a plurality of parallel connected MOS transistors;

two boosting units that perform an operation of boosting by adding the input voltage to a charging voltage of the capacitor; and

a drive unit that causes each of the MOS transistors to perform an ON operation such that all of the MOS transistors are ON at the end of a time series.

2. The charge pump power supply circuit according to claim 1, wherein

each of the MOS transistors have a different ON-state resistance, and

the drive unit causes the MOS transistors to perform the ON operation in a descending order from a MOS transistor that has the highest ON-state resistance.

3. The charge pump power supply circuit according to claim 1, combined ON-state resistances of both the charging units are equal.

4. The charge pump power supply circuit according to claim 1, combined ON-state resistances of both the boosting units are equal.

5. A charge pump power supply circuit comprising:

two charging units that perform an operation of charging a capacitor up to an input voltage;

two boosting units that perform an operation of boosting by adding the input voltage to a charging voltage of the capacitor, at least one of the two boosting units includes a plurality of parallel connected MOS transistors; and

a drive unit that causes each of the MOS transistors to perform an ON operation such that all of the MOS transistors are ON at the end of a time series.

6. The charge pump power supply circuit according to claim 5, wherein

each of the MOS transistors have a different ON-state resistance, and

the drive unit causes the MOS transistors to perform the ON operation in a descending order from a MOS transistor that has the highest ON-state resistance.

7. The charge pump power supply circuit according to claim 5, combined ON-state resistances of both the charging units are equal.

8. The charge pump power supply circuit according to claim 5, combined ON-state resistances of both the boosting units are equal.

9. A charge pump power supply circuit comprising:

two charging units that perform an operation of charging a capacitor up to an input voltage, at least one of the two charging units includes a plurality of parallel connected MOS transistors;

two inverting units that perform an operation of inverting the voltage stored in the capacitor and outputting the inverted voltage; and

a drive unit that causes each of the MOS transistors to perform an ON operation such that all of the MOS transistors are ON at the end of a time series.

10. The charge pump power supply circuit according to claim 9, wherein

each of the MOS transistors have a different ON-state resistance, and

the drive unit causes the MOS transistors to perform the ON operation in a descending order from a MOS transistor that has the highest ON-state resistance.

11. The charge pump power supply circuit according to claim 9, combined ON-state resistances of both the charging units are equal.

12. The charge pump power supply circuit according to claim 9, combined ON-state resistances of both the inverting units are equal.