Class 23 - Digital Storage Oscilloscope - Part 2

Class 23 - Digital Storage Oscilloscope - Part 2:

• One of the important parameter to select Oscilloscope: Bandwidth
• Basic DSO Circuit includes:

• Amplifier
• Track and Hold Circuit
• ADC
• Acquisition circuit
• Digital Converter

Class 22: Digital Storage Oscilloscope - DSO-Part 1

Class 22 - Digital Storage Oscilloscope - Part 1:

Key Point:

• Good Oscilloscope system is its ability to accurately reproduce the waveform
• It is used to detect and debug the issues on the hardware

Email to miycircuits@gmail.com if any questions

Class 21: Differential Signal Routing Method

Class 21: Differential Signal Routing Method

Key Points:

• Isolation with other high speed and switching nodes
• Length Matching and coupling
• Avoid the Routing of the traces over the split
• Termination and impedance

Email to miycircuits@gmail.com if any questions

ROHS - Restriction of Hazardous Substances

Class 20: ROHS - Restriction of Hazardous Substances

 

1. All the countries restriction of the Pb and other substances in the silicon and equipment.

2. Manufacturers are responsible to control design the product with in the allowable limits.

Email to miycircuits@gmail.com if any questions

Class 19: Balanced Differential Signalling

Class 19: Balanced Differential Signalling:

1. For Balanced transmission system, the signals should be routed close to each other.

2. Equal Length.

1. Different type differential signal routing is shown in the above picture.

•          Microstrip
•          Stripline
•          Stripline (Broadside coupled)

1. For the High speed interface it is recommended to route the differential referenced to GND on both side. (Ideal case - electrical validation boards).

2. Length matching tolerances as per the standard guideline

3. Avoid multiple vias on the paths to reduce the impedance mismatch.

Email to miycircuits@gmail.com if any questions

Class 18 : Differential Signalling Part 3

Advantages and Drawbacks of Differential Signalling:

Advantages of differential Signalling:

• Noise insertion to the Single ended and differential signal is shown above.
• Noise coupling will get cancelled @ the receiver for differential signal

• Differential signals are having low voltage level. So radiation level is less on the differential signal. 

Drawbacks on the Differential Signal:

• Need additional wiring.
• High cost and extra circuits 
• Additional routing requirements.

Email to miycircuits@gmail.com if any questions

Class 17: Differential Signalling - Part 2

Class 17: Differential Signalling - Part 2


Noise Margin in Single Ended Signals:

• Single ended signals are distorted by the spurious noise easily.
• Noise margin for the 5V single ended signals shown above.
• Noise margin is high for the single ended signals.

• Latest technology using the low voltage and high speed signals.
• Voltage gone down to 0.8V and
• Differentiall signalling is suitable for the low voltage and high speed signal requirement

Advantages of the Differential Signalling:

• Low voltage swing
• Small noise margin
• High Data rate

Email to miycircuits@gmail.com if you have any questions.

Class 16: Differential signalling

Differential Signalling:

Introduction:

• High Speed Signal transmission needs differential signalling.
• Low voltage transmission of the signal needs differential signalling.
• Differential signalling needs better immunity to noise.

•  Single ended signals transmission is referenced to Ground.
• All the voltage levels measured with respect to ground.
• It needs single conductor for the signal transmission and one common ground.

• Signals are sensed based on the difference of the voltage between the two lines.
• Two conductors are required to transmit the signal + common ground.
• Two conductors should be close to each other and tightly coupled.

• Noise introduced on the differential signals are induced on the both positive and Negative signals.So on the receiver signals noise signal get cancelled.
• Better noise immunity on the differential signals.

• Few typical differential signal routing on the PCB.

For questions and training contact miycircuits@gmail.com

Class 15: Allegro viewer - Layout review

Allegro Viewer- Layout Review Settings

Layer visibility Settings

Mask Enable

Mask TOP: The mask will not present on the visible area.

Paste TOP: Solder paste will be present on the paste top.

Silkscreen TOP: Ref des, connector details will be visible on the layer.

Check out this blog for Hardware Board Design Tutorial.

Class 14: Allegro Viewer - Layout Review Settings

Allegro Viewer - Layout Review Settings

This section explain how to set up a board file prior to layout review:

Class 13: Allegro Viewer - Layout Review Method - Part 01

Allegro Viewer - Layout Review Method

This section explain how to set up a board file prior to review:

DFM - PCB Gerber Checklist

DFM - PCB Gerber Checklist


**Click on the image for readability**

Next Class - PCB Layout Checklist

Class 11: Signal Transmission and distortion

Signal Transmission and Distortion:

Important points:

1. Two types of signal transmission

• Single Ended Signal Transmission
• Differential signalling

Single ended transmission system the signals are transmitted with respect to Ground.

In Differential signalling, two wires are used (P and N) for the signal transmission.

2. Transmitter, transmission line and receiver parasitic create the distortion on the transmitted signals.

Next Class --> Signal Distortion

Class 10:Summary On the High Speed PCB

Summary on the High Speed PCB:

Few Important factors to be considered when designing High Speed PCB: 

• PCB Stack up
• Trace width 
• Trace spacing
• Impedance
• Signal Slew rate
• Signal Frequency
• Interference
• Emission

Next Class: Signal Transmission

Class 09: PCB Stack up

PCB Stack up:

• PCB Material will be selected based on the signal transition time and application operating temperature

Next Class --> Signal Transmission