Renesas FS1012-1002-LQ

Hi, I am currently doing a flow sensor using this FS1012-1002-LQ. The maximum units for the flow rate that the sensor can be measured are 1.0 SLPM. However, based on the data sheet given the flow rate was recorded until 0.5SLPM. Is there any detailed table explains the flow rate from 0.5 to 1.0 SLPM? Also, I am interested to the exact value of the output voltage between each flow rate instead of curve from the graph. Is there any extra data table or graph with larger flow rate frequency to explain it?

  • Hi Kel!

    Thank you for the request. Your request in Renesas sensor is very valuable to us. I would assume that there is no such document apart from the datasheet. Meanwhile I will discuss with my team, if possible, surely, I will provide the details about the characteristics and data.

    Thanks & Regards:


  • Thank you so much,Raja! Hoping that I could get it as soon as possible as I'm rushing for it. 



  • Hi Kel!

    Thank you so much for the patience. I have attached the full flow characteristic for the part no. FS1012-1002-LQ Please go through it and let me know if need any further support. Apart from that we are working on datasheet, we will release latest datasheet, with full flow characteristic, very soon. Thanks again for giving feedback. 



  • Hi Raja,

    Thank you for the quick respond about the graph! As the range value of x axis and y axis are consider big, it's hard for me to really read the graph and form the equation of graph when program it which might affect the sensitivity of my flow meter .May I have the exact data from Renesas to plot this graph?

    Thank you and regards,


  • Or can I get the equation of graph for thermopile 1 and 2?

  • Hi,

    Thank you for the response. Sorry for the delay, I have shared the exact data of flow characteristic please look into that let me know if you have any query or issue.

    Note: Output in milli volt.



  • Hi,

    Thank you for the reply once again. For your information, my project is mainly focus on liquid flow sensor. From the table given, I have certain enquiries related to the data sheet of Renesas FS1012:

    1) From the table, the given data of flow rate for TP1 consists of 14 data but flow rate for TP2 only consists of 8 data. Can I have more value of TP2 for me to calculate the output differential voltage?

    2) Based on the graph below, we can observed that the shape of curves for TP1 and TP2 are different. TP1 is exponential curve while TP2 is slightly exponential than linear curve. In order to generate an output differential signal, I have learnt that the graph must be similar to generate output at positive and negative to cancel out the noise. If I am using differential circuit, which curve should I refer to determine the signal?

    3) If I am planning to construct a single-ended circuit, may I know can TP1 measure liquid flow as well as data sheet state that TP1 is generally used to measure gas flow ?

    4) Figure below shows the analog output curve and equation in the data sheet of Renesas FS1027. Can I have the formula of Renesas FS1012 just like FS1027?

  • Hi,

    Thank you for the detail explanation of your project. 

    Our flow sensor is based on calorimetric principle that produce very high value of signal to noise ratio. It can immune noise as much as possible. Let's reply to your query:

    1.Normally, customers have some instrumentation that controls flow rate, and they calibrate the sensor system using various flow rates and then logging the output. Meanwhile I will also check internally, if more data will be available for 5 V supply voltage, then we will surely provide you apart from that I have also provided more data value for 3.3 V supply voltage (link given below).

    2.If you want to use flow sensor in differential mode, please see the application circuit like that you have to connect TP1 and TP2. Differential mode can be used to measure the more accurate output. This mode minimizes the offset. The output reading of TP1 and TP2 are not closer to each other because of higher heater supply voltage i.e., 5V. For referring to the heater supply, it should make sense that a 5V heater would cause a greater difference than 3.3V, as one side sees a higher temperature difference. Apart from that, I have also provided another data table at 3.3 V in which we can see the reading of TP1 and TP2 are closer to each other.

    FS1012-LQ_CHAR_both_TP_3p3V_20220428.xlsx (


    3.If you measure the liquid flow rate using TP1 then you cannot get more accurate output. see the characteristic as given below and in the datasheet.

    4.Sorry to say that but we don’t have such formula for the part no FS1012.

    We hope this will be helpful to you.