ðiːz ˈɪnstɹəmənts ɑːɹ kˈeɪpəbəl tə fˈiːd kˈɑːnstənt kˈɜːɹənts ɪnðə ɹˈeɪndʒᵻz fɹʌm fjˈuː pˈiːkoʊˌæmpɛɹz pˈiː ɐ tə sˈɛvɹəl ˈæmpɛɹz ɐ; tˈɪpɪkəl kənstɹˈʌkʃən fɔːɹ jˈuːs ɪnðə lˈoʊɚ ɹˈeɪndʒ ʌv fˈiːd kˈɜːɹənts jˈuːsᵻz ˌɑːpɚɹˈeɪʃənəl ˈæmplɪfˌaɪɚz.
These instruments are capable to feed constant currents in the ranges from few picoamperes (pA) to several amperes (A); typical construction for use in the lower range of feed currents uses operational amplifiers.