TLV854x Optimized Operational Amplifiers for Applications with Sensors (ART341E)

   Launched in 2016 but with documentation reviewed in June 2017, the Texas Instruments TLV854x nanopower operational amplifiers of 500 nA RRIO are optimized for sensor applications in wireless systems and low power consumption. This article discusses these operations with sample applications.

   Texas Instruments' TLV854x (double and quad in three types of enclosures) operational amplifiers minimize power consumption in equipment such as motion detectors in safety systems where battery life is an important factor to consider in the design.

   The datasheet of this series of operations can be accessed at: http://www.mouser.com/search/refine.aspx?Ntk=P_MarCom&Ntt=167074387  where your purchase through Mouser Electronics can also be performed.

   In figure 1 we have the wrappers with information about the family.

 

Enclosures and families
Enclosures and families

 

In figure 2 we have an application example in a pyroelectric motion sensor using this operational and also a 2.4 GHz wireless link.

 

Figure 2 - Application circuit
Figure 2 - Application circuit

 

  The important electrical characteristics that we have to highlight are the following:

  - Low current consumption, 500 nA per channel

- Offset voltage of 3.1 mV (max)

- Low bias current: 100 fA

- Gain x passband: 8 kHz

- Supply voltage range: 1.7 to 3.6 V

 - Rail-to-rail output

   The main applications are: motion detector using pyroelectric sensors, microwave motion sensors, gas sensors, ionization smoke alarms, IoT remote sensors, thermostats, medical equipment, glucose monitoring.

   Figure 3 shows the complete diagram of a wireless PIR motion sensor using this component.

 

Figure 3 - PIR motion sensor
Figure 3 - PIR motion sensor

 

   The power is per battery and complete information about its assembly can be obtained in the datasheet. In it we also have the calculations of the components used.

    

 


Circuit Bench