Loop powered transmitter with a single tap data isolation transformer and unipolar voltage converters

A loop-powered transmitter, comprising:

• a power isolation transformer;
• a data isolation transformer including a primary winding and a secondary winding;
• an analog-to-digital converter (ADC) configured to convert an analog signal to a digital value and to provide the digital value through the data isolation transformer;
• a first unipolar voltage converter to receive power through the power isolation transformer and to generate a unipolar operating power to operate the ADC;
• a current limiting resistor connecting the primary winding of the data isolation transformer to ground
• a first microcontroller coupled between the multi-signal interface of the ADC and only one tap of the primary winding of the data isolation transformer;
• a second microcontroller coupled to the tap of the secondary winding of the data isolation transformer, the second microcontroller having a multi-signal interface output;
• a digital-to-analog converter (DAC) having a digital input and a power input, the digital input connecting to the digital multi-signal interface output of the second microcontroller;
• and
• a second unipolar voltage converter coupled to a primary winding of the power isolation transformer and to the power input of the DAC.

A loop-powered transmitter, comprising:

• a data isolation transformer having a primary winding and a secondary winding, the primary winding having a tap;
• an analog-to-digital converter (ADC) having, an analog input lead and a digital multi-signal interface output and a power input;
• a first microcontroller connected to the digital output of the ADC and the tap of the primary winding;
• a power isolation transformer having a primary winding and a secondary winding;
• a first unipolar voltage converter coupled to the secondary winding of the power isolation transformer and the power input of the ADC;
• a second microcontroller coupled to the tap of the secondary winding of the data isolation transformer, the second microcontroller having a multi-signal interface output;
• and
• a digital-to-analog converter (DAC) having a digital input and a power input, the digital multi-signal interface output of the second microcontroller.

A loop-powered transmitter, comprising:

• a power isolation transformer having a primary winding and a secondary winding;
• a data isolation transformer having a primary winding and a secondary winding, the primary winding and the secondary winding of the data isolation transformer each having a tap;
• an analog-to-digital converter (ADC) having, an analog input lead and a digital multi-signal interface output and a power input;
• a first microcontroller connected to the digital output of the ADC and the tap of the primary winding of the data isolation transformer;
• a first unipolar voltage converter coupled to the secondary winding of the power isolation transformer and the power input of the ADC;
• a second microcontroller coupled to the tap of the secondary winding of the data isolation transformer, the second microcontroller having a multi-signal interface output;
• a digital-to-analog converter (DAC) having a digital input and a power input, the digital input connecting to the digital multi-signal interface output of the second microcontroller;
• and
• a second unipolar voltage converter coupled to the primary winding of the power isolation transformer and to the power input of the DAC.