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Contact:
Kang Lee

General Information:
301 975 6602 Telephone
301 990 3851 Facsimile

100 Bureau Drive,
M/S 8220
Gaithersburg, MD 20899-8220

 

Sensor STIM

Sensor STIM

sensor sensor TEDS ADC DI Address logic NCAP
Above is a detailed diagram of a Sensor STIM. Click on any element for further explanation.

What is a STIM?

A Smart Transducer Interface Module(STIM) is a module that contains TEDS, logic to implement the transducer interface, the transducer(s) and any signal conversion or signal conditioning. It consists of 1 to 255 sensors or actuators or any combination of them, DAC, ADC and Digital I/O to interface the sensors or actuators. It also consists of conversion circuitry, address logic, and digital electronics or microprocessors to convert the sensor readings into digital form, or to convert digital output to manipulate actuators to and from the network. The address logic facilitates communication between the STIM and an NCAP. Through the NCAP sensor data is passed to a network. When a STIM contains more than one transducer, it may be referred to as a multichannel STIM or a multi variable STIM. 
When power is applied to the STIM, the information that it carries in the TEDS is made available to the NCAP for local usage, and for distribution to the rest of the network as necessary. Once the TEDS is read, the NCAP knows how fast it can communicate with the STIM, how many channels the STIM has, and the data format of each channel. It can then send information to the STIM, or ask the sensor to perform a reading or get information about readings from the sensor. 


What is a sensor STIM?

A STIM that contains one or more sensors would be called a sensor STIM. If the sensor is a temperature, pressure or flow sensor, it would be called a temperature, pressure or flow STIM respectively. 



How is a sensor STIM used to take a sensor reading?

To Take a Sensor Reading:

  1. Select the channel (the sensor that will be used)
  2. Trigger the sensor
  3. Wait until the STIM indicates a reading is available
  4. Access the raw sensor reading
  5. Convert raw sensor reading into SI units using calibration constants stored in the TEDS.

What can a sensor STIM be used for? 

A sensor STIM can be used to take measurements of any type with the appropriate analog sensors, such as pressure, temperature, air flow, volume, and digital input sensors like switches.