• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 63 subscribers
  • Views 136 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

LM337: why R1=120ohm

BX27
Genius 3870 points
Part Number: LM337

hi 

in datasheet (version L)  page 10 (section 9.2.2), there writes "Choosing R1 = 120 Ω means that about 10.42 mA of current will flow through R1" . Why so? The current flow in R1 should be (Vadj - Vo)/R1. 

Thanks.

  • +1
    TI__Genius 12040 points

    Hello,

             You are correct in stating that the current flow in R1 should be (Vadj - Vo)/R1. In page 8 and section 8.4.1 of the datasheet, it is stated that the device maintains Vadj - Vout = 1.25V. Hence, if R1 = 120Ω, the current flow through R1 will be ~10.41mA (1.25/120).

    Regards,

    Srikanth