• Resolved

OPA2171: Common mode input voltage range

Intellectual 440 points

Replies: 5

Views: 69

Part Number: OPA2171

Hi,

I am using OPA2171AQ1 in my design.

In datasheet the common mode input voltage range(V.CM) is specified as (V-)-0.1 to  (V+)-2 for typical temperature @25dC.

Need to know the range throughout temperature i.e. -40dC to +125dC.

As per datasheet.

with regards,

Siddharth Sangam

  • I think you can use that 2V headroom given the CMRR over temp spec lines, this is another part where the front page says RR input, but overtemp not so much. 

    Michael Steffes

  • Hi Siddharth,

    The OPA171-Q1 device has a common mode voltage range from (V-) - 0.1V to (V+) - 2V over temperature. Please see below.

    The OPA171 uses a complementary pair input stage so the input common mode voltage can go from the negative supply to the positive supply without phase inversion. But when operating above (V+) - 2V  (specified as the Vcm range) there is degraded performance (higher Vos, lower BW, higher noise, etc.). I recommend reading "Op amps with complementary-pair input stages: What are the design trade-offs?" for more information. 

    Thank you,

    Tim Claycomb

  • In reply to Michael Steffes:

    Thanks Michael.

    with regards,                                                                                                                                                                                                                                          Siddharth Sangam

  • In reply to Tim Claycomb:

    Thanks Tim.

    with regards,                                                                                                                                                                                                                                          Siddharth Sangam

  • In reply to Siddharth Sangam:

    I'm glad we could help!