| 摘要 |
PROBLEM TO BE SOLVED: To improve the base current dependence of an output Tr and to realize a low voltage operation by controlling a second reference current source with a transistor for base current correction Tr and setting the bias of 1VBE top respective Tr voltage in the reference voltage sources. SOLUTION: Trs Q1 and Q3 for base current correction operate to enlarge the reference current Iref3 of the second reference current source 2, when the power amplification rateβof Tr is small, namely, when base current is large. When the reference current of a first reference current source 1 is set to be Iref1 , the base current value of current mirror input and output Trs Q2 and Q4 to be Iref2 , the collector current value of TrQ3 for base current correction to be Iref3 -Iref2 , the base current value of TrQ1 for base current correction to be IB, the collector current value of TrQ2 to be IIN, an output current value to be Iout and a value Iref3 -Iref2 to be values IIN and IOUT, IOUT=Iref1 /(1.1/β<2> ) is obtained, the base current dependence of each Tr can be improved. Then, 1VBE bias is set to respective Tr voltage by the first and second reference voltage sources 3 and 4, so as to realize a low-voltage operation.
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