CMOS interpolator for a serializer/deserializer communication application
The present invention relates generally to integrated circuits. More particularly, the present invention provides a circuit and method for regulating a voltage for a high speed serializer/deserializer (SerDes) device. But it will be recognized that the technique can be used for regulating memory devices (e.g., DDR 4 SDRAM devices, DDR4 register devices, DDR4 controller devices), and other high speed data applications. In various embodiments, phase-interpolator is implemented in conjunction with a delay-lock loop (DLL) and an SR latch, where one or more outputs of the DLL is used by the SR latch. Additionally, such techniques can be used for a variety of applications such as network and/or computer storage systems, computer servers, hand held computing devices, portable computing devices, computer systems, network appliances and/or switches, routers, and gateways, and the like.
1. An integrated transceiver circuit device comprising:
a plurality of receivers coupled to a plurality of channels, each of the channels being configured for transmitting asynchronous data to one of the receivers, each of the receivers comprising:
a pre-amplifier device having an input and an output, the input being coupled to a channel associated with a receiver;
a comparator device comprising an input coupled to the output of the pre-amplifier device, and configured to identify one or more binary states;
a phase interpolator device coupled to the comparator device, the phase interpolator device being configured to perform a digital to phase conversion using information from the one or more binary states, the phase interpolator device comprising a phase interpolator core, a set-reset (SR) latch and a feedback loop, the SR latch comprising a set (S) input, a reset (R) input, and an output, the S input being configured to receive signals from the phase interpolator core, the feedback loop being coupled between the output of the SR latch and the R input, the feedback loop being characterized by a phase shift of about 180 degrees, the feedback loop including an operational transconductance amplifier (OTA) for generating a switching signal, the switching signal being associated with the R input; and
a clock data recovery (CDR) circuit coupled to an output of the comparator device and configured to drive the phase interpolator device to synthesize a frequency and phase of a signal from the output of the comparator device; and
a phase lock loop (PLL) device, the PLL device being common to and being coupled to each of the phase interpolator devices in the plurality of receivers.
2. The device of claim 1 wherein the comparator device further comprises a plurality of comparator devices, each of the plurality of comparator devices is coupled to the CDR circuit, each of the plurality of comparator devices being coupled to a separate phase interpolator device associated with the phase interpolator devices.
3. The device of claim 1 wherein the phase interpolator device is characterized using a complimentary metal-oxide semiconductor (CMOS) interpolation that is linear (INL) and is provided to track jitter.
4. The device of claim 1 wherein the phase interpolator device is characterized by a phase linearity and a dynamic performance; and
wherein the phase interpolator device is characterized by a current based mixing to achieve a substantial linearity in a phase to digital code relationship, wherein the phase interpolator device is configured using a CMOS level.
5. The device of claim 1 wherein the plurality of receivers are coupled to a serializer/deserializer (SerDes) device, and coupled to a plurality of transmitters; and
wherein the phase interpolator device is characterized by a CMOS level on an interpolated output.
6. The device of claim 1 wherein the phase interpolator core comprises a pair of mixers configured to mix a first clock and a second clock spaced by 90 Degrees from each other.