Current-controlled CMOS circuit using higher voltage supply in low voltage CMOS process

• US 6,897,697 B2
• Filed: 08/26/2002
• Issued: 05/24/2005
• Est. Priority Date: 06/28/1999
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Fujimori, Ichiro, Yin, Guangming, Hairapetian, Armond
• Primary Examiner(s): Callahan, Timothy P.
• Assistant Examiner(s): Nguyen, Hai L.
• Application Number:
  US10/229,257
• Publication Number:
  US 20020190770A1
• Time in Patent Office: 1,002 Days
• Field of Search: 327201-203, 327/207, 327/208, 327210-212, 327/214, 327/215, 327/219, 327/223, 327115-120, 327/52, 327/65, 327/229, 327/246, 327/319, 327/333, 327/391, 327/437, 327/530, 327/563, 377/47, 377/48, 326 95- 98, 326108-110, 326/121, 326/122, 326/115, 326/119, 326/127, 326/80, 326/81
• US Class Current: 327/210
• CPC Class Codes: H03K 17/693 Switching arrangements with several input- or output-terminals, e.g. multiplexers, distributors logic circuits H03K19/00; code converters H03M5/00, H03M7/00
• CPC Class Codes: H03K 19/09432 with coupled sources or source coupled logic H03K19/096 takes precedence
• CPC Class Codes: H03K 19/215 using field-effect transistors
• CPC Class Codes: H03K 3/356043 with synchronous operation
• CPC Class Codes: H03K 3/3562 of the master-slave type

Abstract

Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C³MOS) logic fabricated in conventional CMOS process technology. An entire family of logic elements including inverter/buffers, level shifters, NAND, NOR, XOR gates, latches, flip-flops and the like are implemented using C³MOS techniques. Optimum balance between power consumption and speed for each circuit application is achieve by combining high speed C³MOS logic with low power conventional CMOS logic. The combined C³MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems. The C³MOS structure enables the use of a power supply voltage that may be larger than the voltage required by the CMOS fabrication process, further enhancing the performance of the circuit.

Claims

1. A metal-oxide-semiconductor field-effect transistor (MOSFET) circuit fabricated on a silicon substrate, comprising:

first circuitry implemented using current-controlled complementary metal-oxide semiconductor (C³MOS) logic wherein differential logic levels are signaled by current steering in one of two or more branches in response to differential logic signals, the first circuitry being configured to process a first logic signal having a first frequency; and

second circuitry coupled to the first circuitry and implemented using conventional complementary metal-oxide-semiconductor (CMOS) logic wherein substantially zero static current is dissipated, the second circuitry being configured to process a second logic signal having a second frequency that is lower than the first frequency,

wherein, the first circuitry is coupled to a first power supply voltage and the second circuitry is coupled to a second power supply voltage that is different than the first power supply voltage.

2. The circuit of claim 1 wherein the first power supply voltage is higher in magnitude than the second power supply voltage.

3. The circuit of claim 2 wherein the second power supply voltage is the maximum power supply voltage specified by CMOS process used to fabricate the circuit.

4. The circuit of claim 1 wherein the second power supply voltage is generated on-chip from the first power supply voltage.

5. The circuit of claim 4 further comprising a voltage generator coupled to the first power supply voltage and configured to generate the second power supply voltage.

6. The circuit of claim 1 wherein the first circuitry comprises one or more C³MOS logic stages, wherein a C³MOS logic stage comprises at least three components including an input transistor coupled between a load device and a tail transistor that are stacked between the first power supply voltage and a lower potential.

7. The circuit of claim 6 wherein the first circuitry further comprises a pre-driver coupled to an input of a C³MOS logic stage, and configured to bias an input signal to the C³MOS logic stage for enhancing speed of operation of the C³MOS logic stage.

8. The circuit of claim 7 wherein the pre-driver reduces a common mode voltage level of the input signal.

9. The circuit of claim 1 wherein the first circuitry comprises an input circuit that is implemented using the C³MOS logic, and is configured to deserialize the first logic signal into a plurality of lower frequency signals.

10. The circuit of claim 9 wherein the second circuitry comprises conventional CMOS logic that is configured to process the plurality of lower frequency signals to generate a plurality of lower frequency processed signals.

11. The circuit of claim 10 wherein the first circuitry further comprises an output circuit that is implemented using the C³MOS logic, and is configured to serialize the plurality of processed signals into one output signal.

12. The circuit of claim 1 wherein the second logic signal comprises a plurality of parallel logic signals, and wherein the first circuitry is configured to serialize the plurality of parallel logic signals into the first differential logic signal.

13. A metal-oxide-semiconductor field-effect transistor (MOSFET) circuit comprising:

a first circuit implemented using current-controlled complementary metal-oxide semiconductor (C³MOS) logic wherein differential logic levels are signaled by current steering in one of two or more branches in response to differential logic signals, the first circuit receiving a first power supply voltage and being configured to process a first logic signal having a first frequency;

a second circuit coupled to the first circuit and implemented using conventional complementary metal-oxide-semiconductor (CMOS) logic wherein substantially zero static current is dissipated, the second circuit receiving a second power supply voltage that is lower in magnitude than the first power supply voltage and being configured to process a second logic signal having a second frequency that is lower than the first frequency; and

a third circuit coupled to the second circuit and implemented using C³MOS logic, the third circuit receiving the first power supply voltage and being configured to process a third logic signal having the first frequency.

14. The MOSFET circuit of claim 13 wherein the first circuit comprises a deserializer that receives the first logic signal having the first frequency and, using a clock signal, generates the second logic signal comprising N logic signals having a second frequency that is lower than the first frequency, where N is an integer greater than one.

15. The MOSFET circuit of claim 14 wherein the second circuit comprises N substantially identical CMOS circuits that respectively process the N logic signals and generate an output signal, the output signal comprising N processed logic signals.

16. The MOSFET circuit of claim 15 wherein the third circuit comprises a serializer that receives the N processed logic signals and converts the N processed logic signals into the third output signal.

17. The MOSFET circuit of claim 16 wherein the second circuit comprises core transceiver circuitry.

18. The MOSFET circuit of claim 13 further comprising a voltage generator coupled to receive the first power supply voltage and configured to generate the second power supply voltage.

19. A method for processing high speed signals using silicon complementary metal-oxide-semiconductor (CMOS) technology, the method comprising:

receiving a first differential logic signal having a first frequency;

processing the first differential logic signal by a first circuit that uses current-controlled complementary metal-oxide semiconductor (C³MOS) logic wherein differential logic levels are signaled by current steering in one of two or more branches in response to differential logic signals;

powering the first circuit using a first power supply voltage;

converting the first differential logic signal into a lower frequency signal;

processing the lower frequency signal by a second circuit that uses standard CMOS logic wherein substantially zero static current is dissipated; and

powering the second circuit using a second power supply voltage that is smaller in magnitude than the first power supply voltage.

20. The method of claim 19 wherein the step of converting comprises deserializing the first differential logic signal into a plurality of lower frequency signals.

21. The method of claim 19 further comprising generating the second power supply voltage from the first power supply voltage.