Apparatus and method for programmable power management in a programmable analog circuit block

• US 8,149,048 B1
• Filed: 08/29/2001
• Issued: 04/03/2012
• Est. Priority Date: 10/26/2000
• Status: Expired due to Term

• Current Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Original Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Inventors: Mar, Monte
• Primary Examiner(s): Tra, Quan
• Application Number:
  US09/943,062
• Time in Patent Office: 3,870 Days
• Field of Search: 327/538, 327/52, 327560-563, 327/108, 330252-254, 330/261
• US Class Current: 327/563
• CPC Class Codes: G06F 11/3652 in-circuit-emulation [ICE] arrangements

Abstract

An apparatus and method for programmable power management in a programmable analog circuit block. Specifically, the present invention describes an operational amplifier circuit that includes current sources that are coupled in parallel. Configuration bits are asserted to selectively enable or selectively disable one or more of the current sources in order to modulate the performance of the operational amplifier circuit block. Selective addition or removal of current sources increases or decreases the amount of current within the operational amplifier and, correspondingly, the speed and power consumption of the operational amplifier. Combinations of asserted configuration bits pass a bias voltage in order enable selected current sources. In one embodiment, the bias voltage can be increased in order to increase the current output of one of the current sources which, correspondingly, increases the speed of the operational amplifier circuit block.

Claims

1. A programmable analog circuit block having programmable power management comprising:

an operational amplifier circuit for driving a load;

a plurality of paired current sources located within said operational amplifier circuit, wherein a first current source in each pair is coupled in a first parallel configuration to a first node that is coupled to transistors receiving input voltages to said operational amplifier circuit, and a second current source in each pair is coupled in a second parallel configuration to an output of said operational amplifier circuit, wherein a ratio of the amount of current between said current sources of each pair of current sources is proportionally equal;

a bias supply signal for generating a given bias voltage; and

a plurality of configuration bits for selectively applying said given bias voltage to an associated pair of current sources in order to modulate the performance of said operational amplifier circuit.

2. The programmable analog circuit block as described in claim 1, wherein said plurality of paired current sources comprises a first and a second pair of current sources.

3. The programmable analog circuit block as described in claim 2, wherein said second pair of current sources provides twice the amount of current in said operational amplifier as said first pair of current sources.

4. The programmable analog circuit block as described in claim 1, further comprising:

a logic decoder for generating a plurality of select signals from said plurality of configuration bits; and

a multiplexor for selectively applying said given bias voltage to said associated pair of current sources based on said plurality of select signals.

5. The programmable analog circuit block as described in claim 4, wherein a voltage level for said bias voltage is increased in order to increase current output from said plurality of current sources.

6. The programmable analog circuit block as described in claim 1, wherein current provided from each pair of current sources is increased by a scaleable ratio to provide scaleable increases in speed of said operational amplifier.

7. The programmable analog circuit block as described in claim 1, wherein a voltage for said bias supply signal is increased for each of said plurality of current sources to increase speed of said operational amplifier.

8. A programmable analog circuit block having programmable power management comprising:

an operational amplifier circuit for driving a load;

a plurality of paired current sources contained within said operational amplifier circuit for increasing current within said operational amplifier circuit, wherein a ratio of the amount of current between current sources of each pair of current sources is proportionally equal;

a bias supply signal for biasing said plurality of paired current sources; and

a plurality of configuration bits for selectively applying said bias supply voltage to one or more of said plurality of paired current sources, based upon a current state of the configuration bits, in order to modulate performance of said operational amplifier circuit.

9. The programmable analog circuit block as described in claim 8, wherein each of said plurality of paired current sources further comprise:

a first current source coupled to a first node that is coupled to transistors receiving an input voltage to said operational amplifier circuit, wherein all first current sources in said plurality of paired current sources are coupled in parallel; and

a second current source coupled to a second node associated with an output voltage to said operational amplifier circuit, wherein all second current sources in said plurality of paired current sources are coupled in parallel.

10. The programmable analog circuit block as described in claim 8, wherein each of said plurality of paired current sources increase current within said operational amplifier in order to increase the speed of said operational amplifier circuit.

11. The programmable analog circuit block as described in claim 8, further comprising:

a logic decoder for generating a plurality of select signals based on said current combination of configuration bits; and

a multiplexor for selectively applying said bias supply voltage to said one or more pairs of current sources based on said plurality of select signals.

12. A method of performing programmable power management in a programmable analog block comprising the steps of:

a) asserting a first group of configuration bits from a plurality of configuration bits; and

b) sending a bias voltage signal, in response to said first group of configuration bits, to a selected group of paired current sources from a plurality of paired current sources in an operational amplifier wherein each configuration bit enables an associated pair of current sources from said plurality of paired current sources and wherein a ration of the amount of current between current sources coupled to an input stage and output stage of said operational amplifier respectively of each pair of current sources is proportionally equal.

13. The method as described in claim 12, wherein said selected group of paired current sources is enabled to increase current in said operational amplifier to increase the operating speed of said operational amplifier.

14. The method as described in claim 12, wherein said method further comprises:

increasing said bias voltage to further increase the operating speed of said operational amplifier.

15. The method as described in claim 12, wherein said plurality of paired current sources are selectable to provide scaleable increases in operating speed for said operational amplifier.

16. The method as described in claim 12, wherein a first current source in each pair is coupled to a first node that is coupled to transistors receiving input voltages to said operational amplifier, and a second current source in each pair is coupled with an output voltage to said operational amplifier, wherein each first current source coupled to said input voltage is coupled in parallel, and wherein each second current source coupled to said output voltage is coupled in parallel.

17. The method as described in claim 16, further comprising the step of:

doubling current output in said second current source in comparison to said first current source of each of said plurality of paired current sources.

18. The method as described in claim 12, comprising the further step of:

disabling a remaining group of paired current sources to deny current to said operational amplifier in order to modulate performance of said operational amplifier, said selected group of paired current sources and said remaining group of paired current sources combined forming said plurality of paired current sources.