PN003 – Input block (ADC)

The BBox has 16 analog inputs for measurements, and each one can be configured separately. The analog input chain is split into a hardware part and a software part that can be configured by the user. A correct configuration of the analog inputs ensures a better working of the control and a proper functioning of the protection system.

This application note presents the configuration of the analog inputs into the hardware and software parts, and how to use them in Simulink and Code Composer Studio.

HARDWARE CONFIGURATION¨

Figure 1.1 : Block diagram of each of the analog inputs.

The figure 1.1 shows the block diagram of the analog inputs. The chain is made of a hardware part and a software part, delimited by the AD conversion. The parameters of the hardware part are the following:

  • The use of a high or low impedance in input;
  • The gain of the amplifier, to fully exploit the input voltage range of the ADC;
  • The use of a low-pass filter on the measurement;
  • Low and high limits, for the fault detection system.

Those hardware parameters can be configured with the frontpanel.

  • Check ref: PN002_Bbox_frontpanel for more information about the configuration of the analog inputs with the frontpanel.

The analog signals go then into an ADC bloc which provides a signed integer of 16 bits. The last part is the conversion of this integer into a float number, which is done in the software part.

c++ CONFIGURATION AND USE

In Code Composer Studio, each analog input channel must be configured in the init function using the following:

SetADCAdjustments(channel, gain/input_gain, offset);

  • channel is the number of the analog input to configure,
  • input_gain is the gain set in the frontpanel,
  • gain is the gain of the sensor,
  • offset is the offset of the sensor.

The gain of DIN sensors and modules’ sensors are provided in “../API/sensors.h”. In the interrupt function, the value of the ADCs can be access with a simple function:

GetADC(channel);

SOFTWARE CONFIGURATION (Simulink)

In Simulink, each analog input channel can be configured by using the ADC bloc provided in the imperix library, as shown in figure 3.1. The sensitivity of imperix’s sensors is also provided.


Figure 3.1: Configuration of an analog input in Simulink.

PN003 – Input block (ADC)

The BBox has 16 analog inputs for measurements, and each one can be configured separately. The analog input chain is split into a hardware part and a software part that can be configured by the user. A correct configuration of the analog inputs ensures a better working of the control and a proper functioning of the protection system.

This application note presents the configuration of the analog inputs into the hardware and software parts, and how to use them in Simulink and Code Composer Studio.

HARDWARE CONFIGURATION¨

Figure 1.1 : Block diagram of each of the analog inputs.

The figure 1.1 shows the block diagram of the analog inputs. The chain is made of a hardware part and a software part, delimited by the AD conversion. The parameters of the hardware part are the following:

  • The use of a high or low impedance in input;
  • The gain of the amplifier, to fully exploit the input voltage range of the ADC;
  • The use of a low-pass filter on the measurement;
  • Low and high limits, for the fault detection system.

Those hardware parameters can be configured with the frontpanel.

  • Check ref: PN002_Bbox_frontpanel for more information about the configuration of the analog inputs with the frontpanel.

The analog signals go then into an ADC bloc which provides a signed integer of 16 bits. The last part is the conversion of this integer into a float number, which is done in the software part.

c++ CONFIGURATION AND USE

In Code Composer Studio, each analog input channel must be configured in the init function using the following:

SetADCAdjustments(channel, gain/input_gain, offset);

  • channel is the number of the analog input to configure,
  • input_gain is the gain set in the frontpanel,
  • gain is the gain of the sensor,
  • offset is the offset of the sensor.

The gain of DIN sensors and modules’ sensors are provided in “../API/sensors.h”. In the interrupt function, the value of the ADCs can be access with a simple function:

GetADC(channel);

SOFTWARE CONFIGURATION (Simulink)

In Simulink, each analog input channel can be configured by using the ADC bloc provided in the imperix library, as shown in figure 3.1. The sensitivity of imperix’s sensors is also provided.


Figure 3.1: Configuration of an analog input in Simulink.