EE463-Static Power Conversion-I

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# EE-463 STATIC POWER CONVERSION-I

# Gate Drivers and Isolation

## Ozan Keysan

## [keysan.me](http://keysan.me)

### Office: C-113 <span class="meta">•</span> Tel: 210 7586

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# Drive Circuits
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### Interface between control and power circuits
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# Requirements
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- ## Supply enough current/voltage for switching (device specific, can be unipolar or bipolar)
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- ## Minimize turn-on, turn-off times
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- ## Isolate the low voltage logic from high voltage side
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- ## In some cases protection is embedded (dead-time, over-current, over-temp etc)

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# Basic Drive Circuits
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### Simple MOSFET Drive Circuit

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# Basic Drive Circuits

### Double emitter-follower drive circuit

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# Basic Drive Circuits

### IC drive with double emitter-follower buffer

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# Low Side vs. High Side Switches

### Buck converter: high-side switch, boost converter: low-side switch

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# High Side Switch

## How can you generate a gate voltage higher than Vs?
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- ## Bootstrap Circuits
- ## Galvanic Isolation (Pulse transformers)
- ## Optocoupler and Floating Power Supply

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# Bootstrap Circuits (Charge Pumps)
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### S1 and S2 are controlled for driving the main switch

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## S1, S2 are ON, S3(diode) becomes ON, Main Switch OFF

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## S1, S2, S3 are OFF, Main Switch ON

<img src="./images/ee463/bootstrap3.png" alt="Drawing" style="width: 500px;"/>
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## Charging a Bootstrap Circuit

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## Discharging a Bootstrap Circuit

<img src="./images/ee463/bootstrap_discharging.png" alt="Drawing" style="width: 750px;"/>
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# A Few Commercial Products:

### [IR2117](https://www.infineon.com/dgdl/Infineon-ir2117-DS-v01_00-EN.pdf?fileId=5546d462533600a4015355c84331168d)

### [MIC5018](http://ww1.microchip.com/downloads/en/DeviceDoc/mic5018.pdf)

### [Infineon Drivers](https://www.infineon.com/cms/en/product/power/gate-driver-ics/high-and-low-side-drivers/#!overview)

### [Analog Devices, MOSFET Drives](https://www.analog.com/en/parametricsearch/11395)

### [Texas Instruments, Half Bridge Drivers](http://www.ti.com/power-management/gate-drivers/half-bridge-drivers/products.html)

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# Useful Readings

### [High Side Low Side Switches](https://engineering.purdue.edu/~ece495/Power_Electronics_Lab/exp5.pdf)

### [TI Training Videos](https://training.ti.com/gate-driver-training-series-low-side-and-h-bridge-gate-driver-fundamentals)

### [Infineon Gate Driver ICs](https://www.infineon.com/dgdl/Infineon-Selection_Guide_Gate_Driver_ICs-SG-v01_00-EN.pdf?fileId=5546d46250cc1fdf015110069cb90f49 )

### [MOSFET Gate Drive Circuit](https://toshiba.semicon-storage.com/info/docget.jsp?did=59460)

### [Firat Deveci, Gate Drivers](http://www.firatdeveci.com/dikkat-high-side-gate-driver/)

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## Isolation
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### Electric Isolation between HV and LV sider is usually required for proper operation and electric safety.

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## Isolation

<img src="http://static.righto.com/images/magsafe/components1-w750.png" alt="Drawing" style="width: 650px;"/>
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## (Galvanic) Isolation: 
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No direct electric contact between two sides

- ## Transformers
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### Isolation Transformers

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## (Galvanic) Isolation:

- ## Pulse Transformer Gate Driver
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<img src="http://www.analog.com/-/media/images/analog-dialogue/en/volume-46/number-4/articles/implementing-an-isolated-half-bridge-gate-driver/gate_driver-fig-03.jpg" alt="Drawing" style="width: 550px;"/>
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## (Galvanic) Isolation:

- ## Pulse Transformer in a IC

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## (Galvanic) Isolation:

- ## Embedded Isolation in Chip
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## (Galvanic) Isolation:

- ## Embedded Isolation in Chip

#### [More Info](http://www.analog.com/en/analog-dialogue/articles/implementing-an-isolated-half-bridge-gate-driver.html)

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# (Galvanic) Isolation

- ## Isolation with Capacitor (Less Common)

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## Optic Isolation
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## Signal is transmitted by light

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## Optic Isolation

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# Isolated Driver Examples

## [IGBT Gate Driver](https://pdf.direnc.net/upload/vla542-01r-datasheet.pdf)
## [IGBT Gate Driver + DC/DC Converter](https://pdf.direnc.net/upload/vla500k-01r-datasheet.pdf)
## [Infineon 2EDF7175F](https://www.infineon.com/cms/en/product/power/gate-driver-ics/2edf7175f/#!overview)
## [Infineon EiceDrivers](https://www.infineon.com/dgdl/Infineon-2EDF7175F-DS-v02_04-EN.pdf?fileId=5546d462636cc8fb0163b09026be3060)

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# Comparison of Isolation Types

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# Application Notes

- ### [Semikron, IGBT Driver Calculation](https://www.semikron.com/dl/service-support/downloads/download/semikron-application-note-igbt-driver-calculation-en-2007-10-31-rev-00/)
- ### [Gate Drive Optocouplers](https://www.vishay.com/docs/81227/81227.pdf)
- ### [Fundamentals of MOSFET and IGBT Gate Driver Circuits](http://www.ti.com/lit/ml/slua618a/slua618a.pdf)
- ### [IGBT and MOSFET Drivers Correctly Calculated](https://gate-driver.power.com/sites/default/files/product_document/application_note/AN-1001_IGBT_and_MOSFET_Drivers_Correctly_Calculated.pdf)
- ### [MOSFET/IGBT Drivers Theory and Applications](http://www.ixysic.com/home/pdfs.nsf/www/AN-401.pdf/$file/AN-401.pdf)
- ### [Noise Reduction and Isolation](https://www.mccdaq.com/PDFs/specs/Noise-Reduction.pdf)
- ### [How to Select Right Galvanic Isolation](https://www.digikey.com/en/articles/techzone/2017/dec/how-select-galvanic-isolation-technology-for-iot-sensors)
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## Considerations/Problems

### From Simulations to Hardware Impementation

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## Not all grounds are same!
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## Be careful when connecting these:

- ### Analog Ground (AGND)
- ### Digital Ground (DGND)
- ### Power Ground (PGND)

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## Use Ground or Power Planes

<img src="https://kicad-info.s3.dualstack.us-west-2.amazonaws.com/original/3X/8/c/8ca7807736f3e06e86c61fb9248471a6574b6c1f.png" alt="Drawing" style="width: 600px;"/>
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## Use Ground or Power Planes

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## Avoid Ground Loops

### Ground loops create a potential difference at difference parts of the ground

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## Avoid Ground Loops

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## Connection of Different Grounds

<img src="https://blogupvertercom.files.wordpress.com/2019/10/mixed_signal.jpg" alt="Drawing" style="width: 600px;"/>
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## Identify High dI/dt paths

### Minimize the length and mutual inductance of these!
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### Be extremely careful with gate signals

- ### Minimize Stray/Parasitic Inductances
- ### Minimize loop inductance
- ### Minimize stray capacitance

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### Be extremely careful with gate signals

### [Connection of Gate Drivers to IGBT and Controller](https://www.semikron-shop.com/out/pictures/wysiwigpro/AN-7002_Connection_of_Gate_Drivers_to_IGBT_and_Controller_rev00.pdf)

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### Place decoupling/filtering capacitors properly

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### Place decoupling/filtering capacitors properly

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### Be careful when placing inductors

- ### Ground plane below can induce eddy currents
- ### Fringing flux can interfere with analog signals

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### Sometimes noise just exist due to measurement

<img src="https://www.powerelectronicsnews.com/wp-content/uploads/sites/3/2018/03/PIDWebinar3-2-12_Good-and-Bad-Measurement-1.jpg" alt="Drawing" style="width: 800px;"/>
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### Sometimes noise just exist due to measurement

<img src="https://www.powerelectronicsnews.com/wp-content/uploads/sites/3/2018/03/PIDWebinar3-2-13_Good-and-Bad-Measurement-2.jpg" alt="Drawing" style="width: 800px;"/>
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## Considerations/Problems

- ### Minimize Cable Inductance/Coupling

#### UTP: Unshielded twisted pair
#### STP: Shielded twisted pair
#### FTP: Foiled twisted pair
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## Considerations/Problems

- ### Shielding and  Minimize Stray Inductance

<img src="./images/ee463/stray_inductance2.jpg" alt="Drawing" style="width: 600px;"/>
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## Considerations/Problems

- ### Reduction of Stray Inductance in Bus Bars

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## Considerations/Problems

- ### Shielding and  Minimize Stray Inductance

- ### [PCB Layout for EMC](https://www.powerelectronicsnews.com/problems-solutions/pcb-layout-for-emc-power-supply-design-tutorial-section-3-1)

- ### [High Speed PCB Layout Techniques](http://www.ti.com/lit/ml/slyp173/slyp173.pdf)

- ### [PCB Design Issues](https://www.analog.com/media/en/training-seminars/design-handbooks/Basic-Linear-Design/Chapter12.pdf)

- ### [PCB Layout Guidelines](https://www.ti.com/lit/ml/slyp762/slyp762.pdf?ts=1704351235039)
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## You can download this presentation from: [keysan.me/ee463](http://keysan.me/ee463)