README.md - third_party/shuttle/sky130/mpw-004/slot-020 - Git at Google


 [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0) [![CI](https://github.com/efabless/caravel_user_project_analog/actions/workflows/user_project_ci.yml/badge.svg)](https://github.com/efabless/caravel_user_project_analog/actions/workflows/user_project_ci.yml) [![Caravan Build](https://github.com/efabless/caravel_user_project_analog/actions/workflows/caravan_build.yml/badge.svg)](https://github.com/efabless/caravel_user_project_analog/actions/workflows/caravan_build.yml)

 ---

 RFCS2/ICD MPW-4 Projects
 ========================

 Backscattering Integration for On-Chip Wireless Power Transfer (WPT) Receivers
 ------------------------------------------------------------------------------

 ### **Introduction**

 Proposed project implement WPT system having the capability of a passive
 backscattering using the single power transfer coils. The design goal of
 project will be to implement an on-chip resonant WPT system that capable
 of harvesting energy from external off chip coils, harvest the megnteic
 energy using an active recitifier and derive a load.

 ![](media/1.png){width="3.5194444444444444in"
 height="1.5597222222222222in"}

 Wireless Power Transmission (WPT) is realized using resonant coils.
 Primary and Secondary coils are loaded with capacitors which are tuned
 at same frequency. Despite of low coupling coefficients MCR-WPT provides
 high power transfer at a single resonant frequency . Active
 rectification was used technique for improving the efficiency
 of [rectification](https://en.wikipedia.org/wiki/Rectifier) by
 replacing [diodes](https://en.wikipedia.org/wiki/Diode) with actively
 controlled switches with or power [bipolar junction
 transistors](https://en.wikipedia.org/wiki/Bipolar_junction_transistor).
 Normal semiconductor diodes have a roughly fixed voltage drop of around
 0.5-1 volts, active rectifiers behave as resistances, and can have
 arbitrarily low voltage drop. The voltage drop across the transistor is
 then much lower, which reduces the power loss. Finally an off chip
 'backscattered signal' is used to change the impedence of coils.

 ### **Circuit Schematic**

 ![](media/2.png){width="5.284722222222222in"
 height="2.3333333333333335in"}

 ### **Layout**

 ![](media/3.png){width="5.115277777777778in"
 height="3.291488407699038in"}

 Bi-Directional Amplifier Architecture for Sub-6 GHz 5G
 ------------------------------------------------------

 ### **Introduction**

 TDD (Time division duplexing) RF front ends operate in such a manner
 that during Transmission, receiver side is isolated using and switch and
 power amplifier is driving the transmission antenna, During Reception,
 transmitter chain is isolated and the received signal from the antenna
 is fed to a low noise amplifier.

 ![](media/4.png){width="2.986111111111111in"
 height="1.7772911198600174in"}
 ![](media/5.png){width="2.9166666666666665in"
 height="1.7161417322834647in"}

 Figure below shows the 2-stage amplifier that is used to provide voltage
 gain in the circuit. In the first stage Transistors M0 and M1 provide
 transconductance. Transistor M1 also reduces current through M2 and
 increases the value of Resistor and drain of M2. Due to this cascode and
 current re-use technique we obtain a large voltage gain. Transistor M4
 is used to provide voltage to current feedback from output to input such
 that the input impedance is governed transistor M4. Transistor M5
 establishes bias voltage for the gate of M0. The second stage combines
 the differential output from stage 1 in such a way that the noise
 contribution of transistor M4 is cancelled.

 ![](media/6.png){width="6.268055555555556in"
 height="3.0560597112860894in"}

 ### **Circuit Schematic**

 ![](media/7.png){width="4.673611111111111in"
 height="2.4419083552055993in"}

 ### **Circuit Layout**

 ![Graphical user interface, diagram Description automatically
 generated](media/8.png){width="6.268055555555556in"
 height="3.242451881014873in"}

 ![A picture containing text, sky, screenshot, document Description
 automatically generated](media/9.png){width="6.268055555555556in"
 height="3.2555555555555555in"}

 ![Chart, line chart Description automatically
 generated](media/10.png){width="6.268055555555556in"
 height="3.5243055555555554in"}

 ![Graphical user interface, application, email Description automatically
 generated](media/11.png){width="6.268055555555556in"
 height="3.2194444444444446in"}

 ![Chart, line chart Description automatically
 generated](media/12.png){width="6.268055555555556in"
 height="3.0419378827646546in"}

 ![](media/13.png){width="6.268055555555556in"
 height="2.898507217847769in"}

 Operational Amplifier
 =====================

 Operational Amplifier is a fundamental analog circuit that is used in
 numerous applications. A conventional two stage opamp is implemented to
 be tested on chip and be further used in ADC circuits.

 ![A picture containing graphical user interface Description
 automatically generated](media/14.png){width="6.268055555555556in"
 height="2.8722222222222222in"}

 ![A picture containing graphical user interface Description
 automatically generated](media/15.png){width="6.268055555555556in"
 height="3.051388888888889in"}

 ![A picture containing graphical user interface Description
 automatically generated](media/16.png){width="6.268055555555556in"
 height="3.665277777777778in"}

 ![A picture containing graphical user interface Description
 automatically generated](media/17.png){width="6.268055555555556in"
 height="3.588888888888889in"}

 ![Diagram, schematic Description automatically
 generated](media/18.png){width="6.268055555555556in"
 height="3.6118055555555557in"}

 ![Chart, histogram Description automatically
 generated](media/19.png){width="6.268055555555556in"
 height="3.61875in"}

   Differential Gain   60 dB
   ------------------- ---------------
   Common Mode Gain    5 dB
   CMRR                55 dB
   Voltage             $\pm \ 0.9$ V
   GBW                 190MHz
   Phase Margin        55 Degrees

 4)  Band Gap Reference
     ------------------

 5)  Bandgap Reference (BGR) is general purpose IP block that generates a
     constant dc voltage independent of all variations including supply,
     temperature and process. **Analog circuits such as** opamps, DC-DC
     converters, voltage control oscillators (VCO) and current mirrors
     used **voltage references extensively.** The figure of merit for
     these systems mainly depends on the accuracy and preciseness of
     voltage reference.

 6)  ![](media/20.png){width="3.3916666666666666in"
     height="3.4916666666666667in"}

 7)  Schematic:

 8)  ![](media/21.emf){width="3.058333333333333in"
     height="3.441666666666667in"}

 9)  Explanation:

 10) The proposed first order BGR is auto start which eliminates the
     start-up circuit. The cascode structure is designed to give a large
     swing, which is not limited by the supply voltage headroom. This
     design does not need a bias circuit. The V~DS~ voltage of MN1 and
     MN2 is utilized to create the bias voltage for MP5 and MP4 instead
     of employing a PMOS transistor. So, a complementary cross-coupled
     structure is designed instead of simple cascode to create the
     V\_Bias (at node B) voltage by itself, as illustrated in Fig. 1-1.
     Furthermore, this architecture improves the gain of cascode stage
     and accurately mirrors the PTAT, improving the temperature
     coefficient and minimising the mismatches between node X and Y.

 11) ![Chart Description automatically generated with medium
     confidence](media/22.png){width="6.268055555555556in"
     height="3.401388888888889in"}

 12) ![Chart, line chart Description automatically
     generated](media/23.png){width="6.266666666666667in"
     height="3.2333333333333334in"}

 13) ![A picture containing chart Description automatically
     generated](media/24.png){width="6.268055555555556in"
     height="2.6840277777777777in"}

 14)

   V ref                     1.21 V
   ------------------------- ----------------------
   Temperature Range         -40 ^o^C to 140 ^o^C
   Supply voltage            2.5 to 4 V
   Temperature Coefficient   10 **ppm/°C**
   Lin regulation            8 mV
   Start-up time             40 µS

	[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0) [![CI](https://github.com/efabless/caravel_user_project_analog/actions/workflows/user_project_ci.yml/badge.svg)](https://github.com/efabless/caravel_user_project_analog/actions/workflows/user_project_ci.yml) [![Caravan Build](https://github.com/efabless/caravel_user_project_analog/actions/workflows/caravan_build.yml/badge.svg)](https://github.com/efabless/caravel_user_project_analog/actions/workflows/caravan_build.yml)

	---

	RFCS2/ICD MPW-4 Projects
	========================

	Backscattering Integration for On-Chip Wireless Power Transfer (WPT) Receivers
	------------------------------------------------------------------------------

	### Introduction

	Proposed project implement WPT system having the capability of a passive
	backscattering using the single power transfer coils. The design goal of
	project will be to implement an on-chip resonant WPT system that capable
	of harvesting energy from external off chip coils, harvest the megnteic
	energy using an active recitifier and derive a load.

	![](media/1.png){width="3.5194444444444444in"
	height="1.5597222222222222in"}

	Wireless Power Transmission (WPT) is realized using resonant coils.
	Primary and Secondary coils are loaded with capacitors which are tuned
	at same frequency. Despite of low coupling coefficients MCR-WPT provides
	high power transfer at a single resonant frequency . Active
	rectification was used technique for improving the efficiency
	of [rectification](https://en.wikipedia.org/wiki/Rectifier) by
	replacing [diodes](https://en.wikipedia.org/wiki/Diode) with actively
	controlled switches with or power [bipolar junction
	transistors](https://en.wikipedia.org/wiki/Bipolar_junction_transistor).
	Normal semiconductor diodes have a roughly fixed voltage drop of around
	0.5-1 volts, active rectifiers behave as resistances, and can have
	arbitrarily low voltage drop. The voltage drop across the transistor is
	then much lower, which reduces the power loss. Finally an off chip
	'backscattered signal' is used to change the impedence of coils.

	### Circuit Schematic

	![](media/2.png){width="5.284722222222222in"
	height="2.3333333333333335in"}

	### Layout

	![](media/3.png){width="5.115277777777778in"
	height="3.291488407699038in"}

	Bi-Directional Amplifier Architecture for Sub-6 GHz 5G
	------------------------------------------------------

	### Introduction

	TDD (Time division duplexing) RF front ends operate in such a manner
	that during Transmission, receiver side is isolated using and switch and
	power amplifier is driving the transmission antenna, During Reception,
	transmitter chain is isolated and the received signal from the antenna
	is fed to a low noise amplifier.

	![](media/4.png){width="2.986111111111111in"
	height="1.7772911198600174in"}
	![](media/5.png){width="2.9166666666666665in"
	height="1.7161417322834647in"}

	Figure below shows the 2-stage amplifier that is used to provide voltage
	gain in the circuit. In the first stage Transistors M0 and M1 provide
	transconductance. Transistor M1 also reduces current through M2 and
	increases the value of Resistor and drain of M2. Due to this cascode and
	current re-use technique we obtain a large voltage gain. Transistor M4
	is used to provide voltage to current feedback from output to input such
	that the input impedance is governed transistor M4. Transistor M5
	establishes bias voltage for the gate of M0. The second stage combines
	the differential output from stage 1 in such a way that the noise
	contribution of transistor M4 is cancelled.

	![](media/6.png){width="6.268055555555556in"
	height="3.0560597112860894in"}

	### Circuit Schematic

	![](media/7.png){width="4.673611111111111in"
	height="2.4419083552055993in"}

	### Circuit Layout

	![Graphical user interface, diagram Description automatically
	generated](media/8.png){width="6.268055555555556in"
	height="3.242451881014873in"}

	![A picture containing text, sky, screenshot, document Description
	automatically generated](media/9.png){width="6.268055555555556in"
	height="3.2555555555555555in"}

	![Chart, line chart Description automatically
	generated](media/10.png){width="6.268055555555556in"
	height="3.5243055555555554in"}

	![Graphical user interface, application, email Description automatically
	generated](media/11.png){width="6.268055555555556in"
	height="3.2194444444444446in"}

	![Chart, line chart Description automatically
	generated](media/12.png){width="6.268055555555556in"
	height="3.0419378827646546in"}

	![](media/13.png){width="6.268055555555556in"
	height="2.898507217847769in"}

	Operational Amplifier
	=====================

	Operational Amplifier is a fundamental analog circuit that is used in
	numerous applications. A conventional two stage opamp is implemented to
	be tested on chip and be further used in ADC circuits.

	![A picture containing graphical user interface Description
	automatically generated](media/14.png){width="6.268055555555556in"
	height="2.8722222222222222in"}

	![A picture containing graphical user interface Description
	automatically generated](media/15.png){width="6.268055555555556in"
	height="3.051388888888889in"}

	![A picture containing graphical user interface Description
	automatically generated](media/16.png){width="6.268055555555556in"
	height="3.665277777777778in"}

	![A picture containing graphical user interface Description
	automatically generated](media/17.png){width="6.268055555555556in"
	height="3.588888888888889in"}

	![Diagram, schematic Description automatically
	generated](media/18.png){width="6.268055555555556in"
	height="3.6118055555555557in"}

	![Chart, histogram Description automatically
	generated](media/19.png){width="6.268055555555556in"
	height="3.61875in"}

	Differential Gain 60 dB
	------------------- ---------------
	Common Mode Gain 5 dB
	CMRR 55 dB
	Voltage $\pm \ 0.9$ V
	GBW 190MHz
	Phase Margin 55 Degrees

	4) Band Gap Reference
	------------------

	5) Bandgap Reference (BGR) is general purpose IP block that generates a
	constant dc voltage independent of all variations including supply,
	temperature and process. Analog circuits such as opamps, DC-DC
	converters, voltage control oscillators (VCO) and current mirrors
	used voltage references extensively. The figure of merit for
	these systems mainly depends on the accuracy and preciseness of
	voltage reference.

	6) ![](media/20.png){width="3.3916666666666666in"
	height="3.4916666666666667in"}

	7) Schematic:

	8) ![](media/21.emf){width="3.058333333333333in"
	height="3.441666666666667in"}

	9) Explanation:

	10) The proposed first order BGR is auto start which eliminates the
	start-up circuit. The cascode structure is designed to give a large
	swing, which is not limited by the supply voltage headroom. This
	design does not need a bias circuit. The V~DS~ voltage of MN1 and
	MN2 is utilized to create the bias voltage for MP5 and MP4 instead
	of employing a PMOS transistor. So, a complementary cross-coupled
	structure is designed instead of simple cascode to create the
	V\_Bias (at node B) voltage by itself, as illustrated in Fig. 1-1.
	Furthermore, this architecture improves the gain of cascode stage
	and accurately mirrors the PTAT, improving the temperature
	coefficient and minimising the mismatches between node X and Y.

	11) ![Chart Description automatically generated with medium
	confidence](media/22.png){width="6.268055555555556in"
	height="3.401388888888889in"}

	12) ![Chart, line chart Description automatically
	generated](media/23.png){width="6.266666666666667in"
	height="3.2333333333333334in"}

	13) ![A picture containing chart Description automatically
	generated](media/24.png){width="6.268055555555556in"
	height="2.6840277777777777in"}

	14)

	V ref 1.21 V
	------------------------- ----------------------
	Temperature Range -40 ^o^C to 140 ^o^C
	Supply voltage 2.5 to 4 V
	Temperature Coefficient 10 ppm/°C
	Lin regulation 8 mV
	Start-up time 40 µS