What is the worst case maximum current consumption of MPX5999D pressure sensor?

[dhanabal_t1]

Hi,

      I am currently working on MPX5999D pressure sensor for medical grade air and O2 pressure sensing. Our maximum pressure range is 95PSI for air and O2. We want to know whether sensor current consumption will vary over pressure range?, during testing we observed current consumption of pressure sensor varied over pressure range. Could you please share us worst case maximum current consumption(considering maximum operating temperature) for entire pressure range and MTBF data. What would be the approximate current consumption at 95psi?

[dhanabal_t1]

Hi Jose,

            Ok. Can you please share us bio compatibility and COC report for this part.

Regards,

Dhanabal T

[reyes]

Hi Dhanabal T,

Unfortunately, I do not have access to the requested data, only quality team will have the bio compatibility and COC report. There are 2 options to reach the quality team to request this data, you can….

1. Create a new support ticket on www.nxp.com/support
2. Contact your NXP Sales representative and ask them for this information, they should be able to contact the quality team for the bio compatibility and COC report.

Regards

Jose

NXP Semiconductors

[dhanabal_t1]

Hi Jose,

                 Thanks for the details.

                  Can you please share long term drift(per year) of full scale output and span voltage change?

                  Want to understand AN3728 "Reliability lifetime Testing" comment on humidity. The THB is also another 60°C at 90% relative humidity for 1000 hrs. These tests prove reliability of Freescale sensors for high humidity and for high temperature, and give an indication of how long the sensor can last in such an environment.  Does it mean this sensor can withstand 90% RH non condensing at 60degC for lifetime? Whether sensor is subjected to any media(ex: air,O2 etc) during this environmental testing. THB data also represents 10 year accelerated lifetime testing?

Regards,

Dhanabal T

[reyes]

Hi Dhanabal T,

There is a normal variation on the output for the pressure sensors for long term applications, according to the datasheet should be ~+/-2.5%, let me mention some recommendation to avoid this drifts or fluctuations:

1. Auto-zero calibration: It’s very important to implement the Auto-zero calibration in our pressure sensors, this is a compensation technique based on sampling the offset of the sensor at reference pressure (atmospheric pressure is a zero reference for a gauge measurement) in order to correct the sensor output for long term offset drift or variation.

Please take a look at the Application Note AN1636 on the following link for the instructions for implement this technique.

AN1636: https://www.nxp.com/docs/en/application-note/AN1636.pdf

2. Temperature: The MPX5999 in temperature compensated over 0° to +85°C, however, below or above this range, the accuracy (variations drifts) is not warranted.

3. Media Compatibility: It’s important to let you know that we do not recommend direct contact with corrosive gases and liquid substances since this could damage the protective gel and this could lead to out of spec device we can only guarantee direct contact with "Clean Dry Air".

4. Power Supply Decoupling and output Filtering: We recommend to use +5.0V to power supply this device and use one 1.0uF and one 0.01uF decoupling capacitors placed close to Vs pin of the pressure sensor, and a 470pF capacitor close to the Vout pin as an output filter capacitor (check figure 4 of the datasheet), or for additional output filtering, please refer to the application note AN1646.

AN1646: https://www.nxp.com/docs/en/application-note/AN1646.pdf

Regards

Jose

NXP Semiconductors

[dhanabal_t1]

Hi Jose,

               Could you please share us below details asap for MPX5999D pressure sensor.

1. Brand of stainless steel metal(ex: AISI 304) part and silicone gel(ex: Wacker 3000 Silicone)

2. Material composition and rating of stainless steel

3. Silicone gel material properties

4. CAS number for silicone gel and stainless steel part

Regards,

Dhanabal T

[dhanabal_t1]

Hi Jose,

               Could you please respond asap for above query. Also share us evidence that MPX5999D sensor is free from Dry Natural Rubber(DNR) and Natural Latex rubber.

Regards,

Dhanabal T

[dhanabal_t1]

Hi Jose,

               Could you please respond on above query. Also we need MPX5999D pressure sensor below highlighted reliability test report for our assessment. As we’re ramping up for formal verification we want to be clarified to finish assessments and start formal verification. Waiting for your response.

Regards,

Dhanabal T

[dhanabal_t1]

Hi Jose,

             What will happen to zero pressure offset value if we seal sensor surface with kapton tape? We want to hide sensor surface with low adhesive kapton tape during board assembly to prevent contamination on sensor surface. Also suggest us recommended adhesive tape to seal sensor surface. 

Any update on previous query's?

Regards,

Dhanabal T

[dhanabal_t1]

Hi Jose,

         Thanks again for your prompt response.

         Can we solder this part by hand solder? Currently our EMS supplier following selective wave soldering but our new supplier don't have this capability. Do you foresee any quality, reliability issue if we solder by hand?

Regards,

Dhanabal T

[reyes]

Hi Dhanabal T,

Yes, there is no problem by soldering the sensors by hand, but you need to take in mind that the Peak Package Body Temperature (PPT) for this part is 220 C° and the Maximum Time at Peak Temperature is 30 seconds. Make sure you do not solder it at temperature above this point and for a time longer than 30 seconds.

You can find this information under “Quality Information” section in the following link: https://www.nxp.com/part/MPX5999D?#/

Regards

Jose

NXP Semiconductors

[dhanabal_t1]

Hi Jose,

               Thanks again for your response.

               We want to understand more on humidity impact in actual use case condition. In our application were sensor is placed in dead end gas path and the sensor is completely enclosed by aluminium metal parts. But in worst case sensor will be exposed to atmosphere through particulate filter. Consider this situation and pressure sensor placement in our product, please let us know the impact of humidity, water droplet, moisture and particulates on pressure sensor performance.

Regards,

Dhanabal T

[reyes]

Hi Dhanabal T,

As long as the particulate filter is working always properly (continue replacing it when needed), there should not be any problem with the sensor. Of course, non-humidity environment is preferred, but, should not affect the system or the sensor performance if there is small amount of humidity, water droplet, moisture and particulates.

Regards

Jose

NXP Semiconductors

[dhanabal_t1]

Hi Jose,

               Thanks for your response.

               What will happen to sensor output voltage if sensor subjected to over pressure for some time(may be couple of secs or min) and recover back to normal operating pressure range? Datasheet says, output voltage will saturate outside pressure range but we want to know once recover back will it work as usual? Is there any offset change or accuracy change because of over pressure effect and will it follow linear characteristics?

Regards,

Dhanabal T

[reyes]

Hi Dhanabal T,

Output voltage of the pressure sensor will be saturated sensor subjected to over pressure, does matter how many time.

After this, when pressure gets back to normal pressure range, the output voltage will be recovered to normal levels without any extra offset or change in the accuracy or linearity or any other effect.

Just take in mind that pressure should never go above 4000kPa, otherwise the device will be permanently damaged.

Regards

Jose

NXP Semiconductors

[dhanabal_t1]

Hi Jose,

              [A1] If sensor follows linear characteristics with P1 side blocked completely with particulates then system will read atmosphere pressure irrespective of pipeline pressure right? How we can avoid this situation?

               [A2] Understood.

Regards,

Dhanabal T

[reyes]

Hi Dhanabal,

Correct, if P1 is blocked completely and P2 is left open to the local atmosphere, you will be reading the local barometric pressure with respect/referenced to the pressure on the sealed P1. If this is not an expected behavior for your application, then you should attach port P1 to the pipeline pressure and this will be used as the reference for the pressure readings.

Regards

Jose

NXP Semiconductors

[dhanabal_t1]

Hi Jose,

1. Understood P1 side should never be lower than pressure on port P2 but situation like P1 side blocked(due to gas contains particulates) at that time P2 side will be directly exposed to atmosphere. What happens to the sensor output at this situation, will it follow linear characteristics?

2. What will be the impact on analog reading if water droplet get in contact with process media(silicon gel)?

2. How many active strain gauges placed inside transducer? Could you please share electrical equivalent of how those strain gauges connected internally?

Thanks again for hot responses!!!

Regards,

Dhanabal T

[reyes]

Hi Dhanabal,

[A1] Correct, sensor’s output will follow the linear characteristic in the mentioned situation.

[A2] Water droplets  in contact with the sensor’s internal silicone gel should not cause a problem as long as it does not degrade the structure of the gel, if the gel gets damaged or degraded, it can leave the wire-bonds exposed, which could cause shorts damaging the sensors.

[A3] Unfortunately we do not have the information about how many active strain gauges are placed inside the transducer, and we cannot share the electrical equivalent of how these gauges are connected. This kind of information can only be shared directly by your NXP Sales representative or NXP FAE with a signed NDA.

Regards

Jose

NXP Semiconductors

[reyes]

Hi,

I requested assistance from the application engineers to solve your question regarding the current consumption, they told me that the current will only change up to 0.5mA over the entire pressure range and based on the typical current, is small in comparison.  They also mentioned that unfortunately, we cannot give any other details about the current other than what’s in the datasheet.

About the MTBF, we do not provide this information for our pressure sensors, but we have requested assistance from the quality engineers team to see if we can generate this information for you, of course, this will take some extra time, I’ll forward on to you but I would not expect anything for at least a week.

Thank you for your patience and understanding.

Regards,

Jose

[reyes]

Hi,

I received the following answer from the Quality engineers:

Qualifications on the family was ran with HTOL of 128 units total over 1,008hrs as the final readpoint.

With a confidence intervals of 95% that gives a MTTF value of ~56,034hrs until a failure would be encountered.

Regards

Jose

NXP Semiconductors