• State
  • Locked Locked
  • Replies 5 replies
  • Subscribers 47 subscribers
  • Views 2017 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

RCV420: -40 to 85deg part

PRAHLAD Supeda
Expert 6150 points
Part Number: RCV420
Other Parts Discussed in Thread: INA828

My customer is using RCV420 4-20mA receiver in Current wheel detector sensor for I-V conversion, they need -40 to 85 degree temperature equivalent part.

Could you please suggest suitable part?

  • 0
    TI__Mastermind 23050 points

    Hi Prahlad,

    Unfortunately the RCV420 is the only integrated current loop receiver we offer. As an alternative you may consider a discrete implementation using an op-amp or instrumentation amplifier (depending on your circuit) that can accommodate a wider temperature range. Here is an example using the INA828:

    4-20mA Receiver RevA.TSC

    Note, in this example I am assuming a load resistance of 220 Ohms, which I have split between RL1 and RL2 to model the common-mode voltage at the resistor. You will need to adjust the input divider and gain accordingly based on the common-mode voltage in your customer's system.

  • 0 in reply to Zak Kaye
    Prodigy 105 points

    Dear Zak how does level shifting happen here? I have a similar application and the bias to the transmitter is an independent 24v supply and my system works on 0-5 volts.

  • 0 in reply to Pawandeep Singh
    TI__Mastermind 23050 points
    Hi Pawandeep,

    In this example the level shifting is accomplished with the -1.25V applied to the reference pin. This voltage needs to be generated from a low impedance source to not disturb the operation of the INA.

    To clarify, if by your system works on 0-5V you mean you have a single +5V supply, then this is not sufficient to generate a 0-5V output. You have to factor in the input and output limitations of the amplifier. You can use the following tool to understand the limitations of your device in various configurations: www.ti.com/.../ina-cmv-calc
  • 0 in reply to Zak Kaye
    TI__Expert 6150 points

    Hi Zak, Thanks for circuit suggestion.

    In RCV420 datasheet under temperature range: specification range is mentioned as 0 to +70degC & operation range is mentioned as -25 to +85degC. And storage range is -45 to +85degC.

    What is the difference between specification & operation range? 

    Can I say RCV420 will be operational & working as expected for -25 to +85degC temperature range?

  • 0 in reply to PRAHLAD Supeda
    TI__Mastermind 23050 points
    Hi Prahlad,

    The specification range is the temperature over which the device is guaranteed to perform within datasheet specs. The operation range defines the range over which the device will still operate without damage, but you may see some degradation in performance with some parameters exceeding the min/max values in the spec table.