LOW POWER HIGH PSRR PVT COMPENSATED BANDGAP AND CURRENT REFERENCE WITH INTERNAL RESISTOR WITH DETECTION/MONITORING CIRCUITS

• US 20130106389A1
• Filed: 10/28/2011
• Published: 05/02/2013
• Est. Priority Date: 10/28/2011
• Status: Abandoned Application

• Current Assignee: Conexant Systems Incorporated (Synaptics Incorporated)
• Original Assignee: Conexant Systems Incorporated (Synaptics Incorporated)
• Inventors: Routray, Dillip Kumar
• Application Number:
  US13/284,833
• Publication Number:
  US 20130106389A1
• Time in Patent Office: Days
• US Class Current: 323/313
• CPC Class Codes: G05F 3/30 Regulators using the difference between the base-emitter voltages of two bipolar transistors operating at different current densities G05F3/26 takes precedence

Abstract

A system for generating a high PSRR bandgap and current reference that includes a bandgap reference circuit for generating a first input and generating a bandgap reference voltage output. A current reference circuit for receiving a second input and generating a reference current. An internal resistor coupled to the first input from bandgap reference circuit and second input of the current reference circuit, wherein the current generated proportional to first input and the second input are generated as a function of the internal resistor. The system also includes a detection/monitoring circuit for bandgap reference output.

Claims

1. A system for generating a bandgap and current reference comprising:

a bandgap reference circuit for generating a proportional first input after producing a bandgap reference voltage output;

a current reference circuit for receiving the proportional first input and a second input and generating a reference current therefrom; and

an internal resistor coupled to the bandgap reference circuit and the current reference circuit, wherein the proportional first input and the second input are generated as a function of the internal resistor.

2. The system of claim 1 further comprising a bandgap voltage detection circuit for receiving the bandgap reference voltage output and the reference current and for determining whether a bandgap voltage has attained a predetermined value.

3. The system of claim 1 further comprising a series connected transistor pair connected in parallel with the internal resistor.

4. The system of claim 1 further comprising a transistor connected in series with the internal resistor.

5. The system of claim 1 wherein the current reference circuit is connected in series with a transistor and the series-connected transistor and current reference circuit is connected in parallel with the internal resistor.

6. The system of claim 1 wherein the bandgap reference circuit further comprises an operational amplifier.

7. The system of claim 1 wherein the bandgap reference circuit further comprises an operational amplifier with chopper stabilization.

8. The system of claim 1 wherein the bandgap reference circuit further comprises one or more bipolar junction transistors.

9. The system of claim 1 wherein the bandgap reference circuit further comprises one or more bipolar junction transistors and one or more field effect transistors.

10. The system of claim 1 wherein the bipolar junction transistors are operated as diodes.

11. A system for generating a bandgap and current reference comprising:

a bandgap reference circuit for generating a bandgap reference voltage output and a proportional first input;

means for receiving a second input and generating a reference current; and

an internal resistor receiving the proportional first input from the bandgap reference circuit and the means for generating the reference current, wherein the reference current is a function of the internal resistor.

12. The system of claim 11 further comprising a bandgap voltage detection/monitoring circuit for receiving the bandgap reference voltage output and determining whether a bandgap voltage has attained a predetermined value.

13. The system of claim 11 further comprising a series connected transistor pair connected in parallel with the internal resistor.

14. The system of claim 11 further comprising a transistor connected in series with the internal resistor.

15. The system of claim 11 wherein the bandgap reference circuit further comprises an operational amplifier.

16. The system of claim 11 wherein the bandgap reference circuit further comprises an operational amplifier with chopper stabilization.

17. The system of claim 11 wherein the bandgap reference circuit further comprises one or more bipolar junction transistors.

18. The system of claim 11 wherein the bandgap reference circuit further comprises one or more bipolar junction transistors and one or more field effect transistors.

19. The system of claim 11 wherein the bipolar junction transistors are operated as diodes.

20. A system for generating a bandgap and current reference comprising:

a bandgap reference circuit for generating a first input and a bandgap reference voltage output;

a current reference circuit for receiving a second input and generating a reference current;

an internal resistor coupled to the bandgap reference circuit and the current reference circuit, wherein the reference current is generated as a function of the internal resistor, the first input and the second input;

a bandgap voltage detection circuit for receiving the bandgap reference voltage output and determining whether a bandgap voltage has attained a predetermined value;

a series connected transistor pair connected in parallel with the internal resistor;

a parallel-connected transistor pair connected in series with the internal resistor and the series connected transistor pair;

wherein the current reference circuit is connected in series with a transistor and the series-connected transistor and current reference circuit is connected in parallel with the internal resistor;

wherein the bandgap reference circuit further comprises;

an operational amplifier with chopper stabilization;

one or more bipolar junction transistors;

one or more field effect transistors; and

wherein the bipolar junction transistors are operated as diodes.