METHOD AND APPARATUS FOR GENERATING A CHARGE PUMP CONTROL SIGNAL

• US 20170358329A1
• Filed: 06/07/2017
• Published: 12/14/2017
• Est. Priority Date: 06/08/2016
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Inventors: Goumballa, Birama, Pavao Moreira, Cristian, Savary, Pierre Pascal
• Granted Patent: US 10,381,051 B2
• Time in Patent Office: Days
• CPC Class Codes: G05F 1/10 Regulating voltage or current G05F1/02 takes precedence; for electric railways B60M3/02
• CPC Class Codes: G11C 5/145 Applications of charge pumps; Boosted voltage circuits; Clamp circuits therefor G11C5/141 takes precedence
• CPC Class Codes: H02M 1/0003 Details of control, feedback or regulation circuits
• 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: H03K 3/03 Astable circuits
• CPC Class Codes: H03L 7/0895 Details of the current generators H03L7/0893 takes precedence
• CPC Class Codes: H03L 7/0896 the current generators being controlled by differential up-down pulses

Abstract

A charge pump driver circuit (320) arranged to output a charge pump control signal (325). The charge pump driver circuit (320) includes a bias current source component (330) arranged to generate a bias current (335), a control stage (340) and an output stage (350). The control stage (340) is coupled to the bias current source component (330) and arranged to receive the bias current (335). The control stage (340) is further arranged to receive an input signal (215) and to generate a control current signal (345) proportional to the bias current (335) in accordance with the input signal (215). The output stage (350) is arranged to receive the control current signal (345) generated by the control stage (340) and to generate the charge pump control voltage signal (325) based on the control current signal (345) generated by the control stage (340). The bias current source component (330) is arranged to vary the bias current (335) in response to variations in temperature.

Claims

1. A charge pump driver circuit arranged to output a charge pump control voltage signal, the charge pump driver circuit comprising:

a bias current source component arranged to generate a bias current;

a control stage coupled to the bias current source component and arranged to receive the bias current, the control stage is further arranged to receive an input signal and to generate a control current signal proportional to the bias current in accordance with the input signal; and

an output stage arranged to receive the control current signal generated by the control stage and to generate the charge pump control voltage signal based on the control current signal generated by the control stage,

wherein the bias current source component is arranged to vary the bias current in response to variations in temperature.

2. The charge pump driver circuit of claim 1, wherein the control stage comprises a control current circuit arranged to receive the input signal and the bias current generated by the bias current source component and to convert voltage pulses within the input signal into current pulses comprising a constant amplitude ratio with the bias current;

and

the control stage is arranged to output as the control current signal the current pulses generated by the control current circuit.

3. The charge pump driver circuit of claim 2, wherein the control current circuit comprises:

a first current mirror arrangement comprising a reference device through which the bias current flows, a first mirror device through which a first mirror current is regulated, and a second mirror device through which a second mirror current is regulated;

a second current mirror arrangement comprising a reference device through which the second mirror current flows, and a mirror device through which a source current is regulated, the mirror device of the second current mirror arrangement being coupled between a supply node and an output node of the control current circuit; and

a bipolar transistor having an emitter terminal coupled to the first mirror device of the first current mirror arrangement, a collector terminal coupled to the output node of the control current circuit and a base terminal coupled to the input signal.

4. The charge pump driver circuit of claim 1, wherein the output stage comprises:

a bipolar transistor comprising a collector terminal coupled to a supply node of the charge pump driver circuit, an emitter terminal coupled to an output node of the charge pump driver circuit and a base terminal operably coupled to an output node of the control current circuit; and

a component network coupled between the output node of the control current circuit and a reference voltage node and arranged to convert the control current signal generated by the control stage into a control voltage signal at the base terminal of the bipolar transistor.

5. The charge pump driver circuit of claim 4, wherein the component network comprises a bipolar transistor coupled in series with at least one resistive element, with a base terminal thereof coupled to a collector terminal thereof.

6. The charge pump driver circuit of claim 1, wherein the bias current source component is arranged to generate the bias current having a negative slope temperature profile.

7. The charge pump driver circuit of claim 1, wherein the bias current source component (330) is arranged to generate the bias current having a multi-region temperature profile.

8. The charge pump driver circuit of claim 1, wherein the bias current source component is arranged to generate the bias current comprising a current component inversely proportional to absolute temperature

9. A phase-locked loop, comprising a charge pump circuit and a charge pump driver circuit according to claim 1, arranged to output a charge pump control voltage signal to the charge pump circuit.

10. A method of generating a charge pump control voltage signal;

the method comprising;

receiving an input signal;

generating a temperature dependent bias current;

generating a control current signal proportional to the temperature dependent bias current in accordance with the input signal; and

generating the charge pump voltage control signal based on the control current signal.

11. The method of claim 10, wherein the control current signal is generated by converting voltage pulses within the input signal into current pulses comprising a constant amplitude ratio with the bias current, and outputting as the control current signal the current pulses generated by the control current circuit.

12. The method of claim 10, comprising generating the bias current having a negative slope temperature profile.

13. The method of claim 10, comprising generating the bias current comprising a current component inversely proportional to absolute temperature.