12-26-2019

There are many different types of PCB designs and constructions that can be used as a test vehicle to evaluate electrical properties. John Coonrod explains how a proper test vehicle to compare different circuit materials would be a design and construction that takes into consideration the different material properties and have the least amount of PCB fabrication variables that can impact the results.

06-27-2019

There are a few things to consider about glass weave effect. One point of interest is when a laminate is using more than one layer of glass, the glass weave effect is somewhat dampened due to an averaging effect of the glass weave layers with their random alignment to each other. Another point of interest would be when a conductor is much larger than the geometry of the glass bundles, knuckles, and open area. Then, the conductor will experience an averaging of these different Dk values from the glass weave effect. This is typically not a problem for electrical performance.

05-10-2019

The circuit is a microstrip with a signal conductor on the top copper plane and a ground plane on the bottom of the circuit. Additionally, the concept of skin depth and wave propagation should be considered. Skin depth is the depth within the cross-sectional area of the copper where the majority of the RF current resides and is dependent on frequency. At lower frequencies, the RF current will have a thicker skin depth and use more of the conductor. At higher frequencies, the skin depth is thinner, and less of the conductor is used by the RF current.

04-04-2019

The smaller wavelengths of mmWave frequencies tend to highlight circuit material anomalies at those higher frequencies—anomalies that can also influence the radio frequency (RF) performance of the circuit. Such material anomalies include variations in dielectric thickness, dielectric constant (Dk), copper conductor width and spacing, and copper conductor plated thickness. For mmWave circuits, even small variations in these key material properties can impact electrical performance. Fortunately, flexible circuit technology is typically well controlled for thickness compared to thicker, more rigid circuit board materials.

12-26-2019

There are many different types of PCB designs and constructions that can be used as a test vehicle to evaluate electrical properties. John Coonrod explains how a proper test vehicle to compare different circuit materials would be a design and construction that takes into consideration the different material properties and have the least amount of PCB fabrication variables that can impact the results.

06-27-2019

There are a few things to consider about glass weave effect. One point of interest is when a laminate is using more than one layer of glass, the glass weave effect is somewhat dampened due to an averaging effect of the glass weave layers with their random alignment to each other. Another point of interest would be when a conductor is much larger than the geometry of the glass bundles, knuckles, and open area. Then, the conductor will experience an averaging of these different Dk values from the glass weave effect. This is typically not a problem for electrical performance.

05-10-2019

The circuit is a microstrip with a signal conductor on the top copper plane and a ground plane on the bottom of the circuit. Additionally, the concept of skin depth and wave propagation should be considered. Skin depth is the depth within the cross-sectional area of the copper where the majority of the RF current resides and is dependent on frequency. At lower frequencies, the RF current will have a thicker skin depth and use more of the conductor. At higher frequencies, the skin depth is thinner, and less of the conductor is used by the RF current.

04-04-2019

The smaller wavelengths of mmWave frequencies tend to highlight circuit material anomalies at those higher frequencies—anomalies that can also influence the radio frequency (RF) performance of the circuit. Such material anomalies include variations in dielectric thickness, dielectric constant (Dk), copper conductor width and spacing, and copper conductor plated thickness. For mmWave circuits, even small variations in these key material properties can impact electrical performance. Fortunately, flexible circuit technology is typically well controlled for thickness compared to thicker, more rigid circuit board materials.

12-26-2019

There are many different types of PCB designs and constructions that can be used as a test vehicle to evaluate electrical properties. John Coonrod explains how a proper test vehicle to compare different circuit materials would be a design and construction that takes into consideration the different material properties and have the least amount of PCB fabrication variables that can impact the results.

06-27-2019

There are a few things to consider about glass weave effect. One point of interest is when a laminate is using more than one layer of glass, the glass weave effect is somewhat dampened due to an averaging effect of the glass weave layers with their random alignment to each other. Another point of interest would be when a conductor is much larger than the geometry of the glass bundles, knuckles, and open area. Then, the conductor will experience an averaging of these different Dk values from the glass weave effect. This is typically not a problem for electrical performance.

05-10-2019

The circuit is a microstrip with a signal conductor on the top copper plane and a ground plane on the bottom of the circuit. Additionally, the concept of skin depth and wave propagation should be considered. Skin depth is the depth within the cross-sectional area of the copper where the majority of the RF current resides and is dependent on frequency. At lower frequencies, the RF current will have a thicker skin depth and use more of the conductor. At higher frequencies, the skin depth is thinner, and less of the conductor is used by the RF current.

04-04-2019

The smaller wavelengths of mmWave frequencies tend to highlight circuit material anomalies at those higher frequencies—anomalies that can also influence the radio frequency (RF) performance of the circuit. Such material anomalies include variations in dielectric thickness, dielectric constant (Dk), copper conductor width and spacing, and copper conductor plated thickness. For mmWave circuits, even small variations in these key material properties can impact electrical performance. Fortunately, flexible circuit technology is typically well controlled for thickness compared to thicker, more rigid circuit board materials.

12-26-2019

There are many different types of PCB designs and constructions that can be used as a test vehicle to evaluate electrical properties. John Coonrod explains how a proper test vehicle to compare different circuit materials would be a design and construction that takes into consideration the different material properties and have the least amount of PCB fabrication variables that can impact the results.

06-27-2019

There are a few things to consider about glass weave effect. One point of interest is when a laminate is using more than one layer of glass, the glass weave effect is somewhat dampened due to an averaging effect of the glass weave layers with their random alignment to each other. Another point of interest would be when a conductor is much larger than the geometry of the glass bundles, knuckles, and open area. Then, the conductor will experience an averaging of these different Dk values from the glass weave effect. This is typically not a problem for electrical performance.

05-10-2019

The circuit is a microstrip with a signal conductor on the top copper plane and a ground plane on the bottom of the circuit. Additionally, the concept of skin depth and wave propagation should be considered. Skin depth is the depth within the cross-sectional area of the copper where the majority of the RF current resides and is dependent on frequency. At lower frequencies, the RF current will have a thicker skin depth and use more of the conductor. At higher frequencies, the skin depth is thinner, and less of the conductor is used by the RF current.

04-04-2019

The smaller wavelengths of mmWave frequencies tend to highlight circuit material anomalies at those higher frequencies—anomalies that can also influence the radio frequency (RF) performance of the circuit. Such material anomalies include variations in dielectric thickness, dielectric constant (Dk), copper conductor width and spacing, and copper conductor plated thickness. For mmWave circuits, even small variations in these key material properties can impact electrical performance. Fortunately, flexible circuit technology is typically well controlled for thickness compared to thicker, more rigid circuit board materials.

11-05-2015

A variety of plated finishes are used in the PCB industry. Depending on the circuit construction and other variables, the plated finish can cause an increase in PCB insertion loss. The plated finish used on the outer ground planes of a stripline circuit have minimal or no impact on insertion loss. However, microstrip or grounded coplanar waveguide circuits, which are common on the outer layers of multilayer high-frequency PCBs, can be impacted by the plated finish for increasing the insertion loss.

09-02-2015

The PCB laminates used for high-frequency applications possess several unique attributes that are distinctly different than that of FR-4 materials. Obviously, the electrical properties are better for high-frequency laminates than FR-4; however there are many other beneficial characteristics which may be less obvious for those unfamiliar with these specialty laminates. These other properties lead technologists to sometimes use high-frequency laminates for applications that are not high-frequency.

07-15-2015

Flexible circuits are designed to be bendable, but bending rigid PCBs is a little unusual. However, many applications that do not use flex circuit technology will also require bending and forming the circuit. Some of these applications use high-frequency circuit materials to create a circuit in a form that enables improved antenna functionality. Another application involves wrapping a circuit around a structure, which sometimes functions as an antenna as well. John Coonrod explains.

05-06-2015

I often hear this question: “How much RF power can be applied to a high-frequency PCB?” My answer sometimes surprises engineers. I tell them that they can put as much RF power into the PCB as they want, with the assumption that the PCB does not exceed its maximum operating temperature (MOT). MOT refers to the maximum temperature to which a circuit can be exposed without degradation of critical properties.

03-04-2015

In the past, one of OEM customers’ main concerns when dealing with their PCB fabricators was characteristic impedance. Many times, a PCB design is considered controlled impedance and the PCB fabricator is held to a specification for impedance control.

01-07-2015

Columnist John Coonrod writes, "The title may be confusing for many technologists accustomed to dealing with electrical issues in traditional PCBs, but if you design PCBs that operate at microwave frequencies, it makes perfect sense. With microwave PCB design, it is not uncommon to have a conductor run come to a stop, followed by a space, followed by another conductor run, with the RF energy propagating through the discontinuity without the slightest problem."

11-05-2015

A variety of plated finishes are used in the PCB industry. Depending on the circuit construction and other variables, the plated finish can cause an increase in PCB insertion loss. The plated finish used on the outer ground planes of a stripline circuit have minimal or no impact on insertion loss. However, microstrip or grounded coplanar waveguide circuits, which are common on the outer layers of multilayer high-frequency PCBs, can be impacted by the plated finish for increasing the insertion loss.

09-02-2015

The PCB laminates used for high-frequency applications possess several unique attributes that are distinctly different than that of FR-4 materials. Obviously, the electrical properties are better for high-frequency laminates than FR-4; however there are many other beneficial characteristics which may be less obvious for those unfamiliar with these specialty laminates. These other properties lead technologists to sometimes use high-frequency laminates for applications that are not high-frequency.

07-15-2015

Flexible circuits are designed to be bendable, but bending rigid PCBs is a little unusual. However, many applications that do not use flex circuit technology will also require bending and forming the circuit. Some of these applications use high-frequency circuit materials to create a circuit in a form that enables improved antenna functionality. Another application involves wrapping a circuit around a structure, which sometimes functions as an antenna as well. John Coonrod explains.

05-06-2015

I often hear this question: “How much RF power can be applied to a high-frequency PCB?” My answer sometimes surprises engineers. I tell them that they can put as much RF power into the PCB as they want, with the assumption that the PCB does not exceed its maximum operating temperature (MOT). MOT refers to the maximum temperature to which a circuit can be exposed without degradation of critical properties.

03-04-2015

In the past, one of OEM customers’ main concerns when dealing with their PCB fabricators was characteristic impedance. Many times, a PCB design is considered controlled impedance and the PCB fabricator is held to a specification for impedance control.

01-07-2015

Columnist John Coonrod writes, "The title may be confusing for many technologists accustomed to dealing with electrical issues in traditional PCBs, but if you design PCBs that operate at microwave frequencies, it makes perfect sense. With microwave PCB design, it is not uncommon to have a conductor run come to a stop, followed by a space, followed by another conductor run, with the RF energy propagating through the discontinuity without the slightest problem."

11-05-2015

A variety of plated finishes are used in the PCB industry. Depending on the circuit construction and other variables, the plated finish can cause an increase in PCB insertion loss. The plated finish used on the outer ground planes of a stripline circuit have minimal or no impact on insertion loss. However, microstrip or grounded coplanar waveguide circuits, which are common on the outer layers of multilayer high-frequency PCBs, can be impacted by the plated finish for increasing the insertion loss.

09-02-2015

The PCB laminates used for high-frequency applications possess several unique attributes that are distinctly different than that of FR-4 materials. Obviously, the electrical properties are better for high-frequency laminates than FR-4; however there are many other beneficial characteristics which may be less obvious for those unfamiliar with these specialty laminates. These other properties lead technologists to sometimes use high-frequency laminates for applications that are not high-frequency.

07-15-2015

Flexible circuits are designed to be bendable, but bending rigid PCBs is a little unusual. However, many applications that do not use flex circuit technology will also require bending and forming the circuit. Some of these applications use high-frequency circuit materials to create a circuit in a form that enables improved antenna functionality. Another application involves wrapping a circuit around a structure, which sometimes functions as an antenna as well. John Coonrod explains.

05-06-2015

I often hear this question: “How much RF power can be applied to a high-frequency PCB?” My answer sometimes surprises engineers. I tell them that they can put as much RF power into the PCB as they want, with the assumption that the PCB does not exceed its maximum operating temperature (MOT). MOT refers to the maximum temperature to which a circuit can be exposed without degradation of critical properties.

03-04-2015

In the past, one of OEM customers’ main concerns when dealing with their PCB fabricators was characteristic impedance. Many times, a PCB design is considered controlled impedance and the PCB fabricator is held to a specification for impedance control.

01-07-2015

Columnist John Coonrod writes, "The title may be confusing for many technologists accustomed to dealing with electrical issues in traditional PCBs, but if you design PCBs that operate at microwave frequencies, it makes perfect sense. With microwave PCB design, it is not uncommon to have a conductor run come to a stop, followed by a space, followed by another conductor run, with the RF energy propagating through the discontinuity without the slightest problem."

11-05-2015

A variety of plated finishes are used in the PCB industry. Depending on the circuit construction and other variables, the plated finish can cause an increase in PCB insertion loss. The plated finish used on the outer ground planes of a stripline circuit have minimal or no impact on insertion loss. However, microstrip or grounded coplanar waveguide circuits, which are common on the outer layers of multilayer high-frequency PCBs, can be impacted by the plated finish for increasing the insertion loss.

09-02-2015

The PCB laminates used for high-frequency applications possess several unique attributes that are distinctly different than that of FR-4 materials. Obviously, the electrical properties are better for high-frequency laminates than FR-4; however there are many other beneficial characteristics which may be less obvious for those unfamiliar with these specialty laminates. These other properties lead technologists to sometimes use high-frequency laminates for applications that are not high-frequency.

07-15-2015

Flexible circuits are designed to be bendable, but bending rigid PCBs is a little unusual. However, many applications that do not use flex circuit technology will also require bending and forming the circuit. Some of these applications use high-frequency circuit materials to create a circuit in a form that enables improved antenna functionality. Another application involves wrapping a circuit around a structure, which sometimes functions as an antenna as well. John Coonrod explains.

05-06-2015

I often hear this question: “How much RF power can be applied to a high-frequency PCB?” My answer sometimes surprises engineers. I tell them that they can put as much RF power into the PCB as they want, with the assumption that the PCB does not exceed its maximum operating temperature (MOT). MOT refers to the maximum temperature to which a circuit can be exposed without degradation of critical properties.

03-04-2015

In the past, one of OEM customers’ main concerns when dealing with their PCB fabricators was characteristic impedance. Many times, a PCB design is considered controlled impedance and the PCB fabricator is held to a specification for impedance control.

01-07-2015

Columnist John Coonrod writes, "The title may be confusing for many technologists accustomed to dealing with electrical issues in traditional PCBs, but if you design PCBs that operate at microwave frequencies, it makes perfect sense. With microwave PCB design, it is not uncommon to have a conductor run come to a stop, followed by a space, followed by another conductor run, with the RF energy propagating through the discontinuity without the slightest problem."

11-05-2015

A variety of plated finishes are used in the PCB industry. Depending on the circuit construction and other variables, the plated finish can cause an increase in PCB insertion loss. The plated finish used on the outer ground planes of a stripline circuit have minimal or no impact on insertion loss. However, microstrip or grounded coplanar waveguide circuits, which are common on the outer layers of multilayer high-frequency PCBs, can be impacted by the plated finish for increasing the insertion loss.

09-02-2015

The PCB laminates used for high-frequency applications possess several unique attributes that are distinctly different than that of FR-4 materials. Obviously, the electrical properties are better for high-frequency laminates than FR-4; however there are many other beneficial characteristics which may be less obvious for those unfamiliar with these specialty laminates. These other properties lead technologists to sometimes use high-frequency laminates for applications that are not high-frequency.

07-15-2015

Flexible circuits are designed to be bendable, but bending rigid PCBs is a little unusual. However, many applications that do not use flex circuit technology will also require bending and forming the circuit. Some of these applications use high-frequency circuit materials to create a circuit in a form that enables improved antenna functionality. Another application involves wrapping a circuit around a structure, which sometimes functions as an antenna as well. John Coonrod explains.

05-06-2015

I often hear this question: “How much RF power can be applied to a high-frequency PCB?” My answer sometimes surprises engineers. I tell them that they can put as much RF power into the PCB as they want, with the assumption that the PCB does not exceed its maximum operating temperature (MOT). MOT refers to the maximum temperature to which a circuit can be exposed without degradation of critical properties.

03-04-2015

In the past, one of OEM customers’ main concerns when dealing with their PCB fabricators was characteristic impedance. Many times, a PCB design is considered controlled impedance and the PCB fabricator is held to a specification for impedance control.

01-07-2015

Columnist John Coonrod writes, "The title may be confusing for many technologists accustomed to dealing with electrical issues in traditional PCBs, but if you design PCBs that operate at microwave frequencies, it makes perfect sense. With microwave PCB design, it is not uncommon to have a conductor run come to a stop, followed by a space, followed by another conductor run, with the RF energy propagating through the discontinuity without the slightest problem."

11-05-2015

A variety of plated finishes are used in the PCB industry. Depending on the circuit construction and other variables, the plated finish can cause an increase in PCB insertion loss. The plated finish used on the outer ground planes of a stripline circuit have minimal or no impact on insertion loss. However, microstrip or grounded coplanar waveguide circuits, which are common on the outer layers of multilayer high-frequency PCBs, can be impacted by the plated finish for increasing the insertion loss.

09-02-2015

The PCB laminates used for high-frequency applications possess several unique attributes that are distinctly different than that of FR-4 materials. Obviously, the electrical properties are better for high-frequency laminates than FR-4; however there are many other beneficial characteristics which may be less obvious for those unfamiliar with these specialty laminates. These other properties lead technologists to sometimes use high-frequency laminates for applications that are not high-frequency.

07-15-2015

Flexible circuits are designed to be bendable, but bending rigid PCBs is a little unusual. However, many applications that do not use flex circuit technology will also require bending and forming the circuit. Some of these applications use high-frequency circuit materials to create a circuit in a form that enables improved antenna functionality. Another application involves wrapping a circuit around a structure, which sometimes functions as an antenna as well. John Coonrod explains.

05-06-2015

I often hear this question: “How much RF power can be applied to a high-frequency PCB?” My answer sometimes surprises engineers. I tell them that they can put as much RF power into the PCB as they want, with the assumption that the PCB does not exceed its maximum operating temperature (MOT). MOT refers to the maximum temperature to which a circuit can be exposed without degradation of critical properties.

03-04-2015

In the past, one of OEM customers’ main concerns when dealing with their PCB fabricators was characteristic impedance. Many times, a PCB design is considered controlled impedance and the PCB fabricator is held to a specification for impedance control.

01-07-2015

Columnist John Coonrod writes, "The title may be confusing for many technologists accustomed to dealing with electrical issues in traditional PCBs, but if you design PCBs that operate at microwave frequencies, it makes perfect sense. With microwave PCB design, it is not uncommon to have a conductor run come to a stop, followed by a space, followed by another conductor run, with the RF energy propagating through the discontinuity without the slightest problem."