| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an overcurrent detection circuit that is less susceptible to temperature changes. <P>SOLUTION: In the overcurrent detection circuit including a diode string 55, an anode end of the diode string 55 is connected to a source terminal of a depletion type transistor DNM1, and a cathode end of the diode string 55 and a substrate of the depletion type transistor DNM1 are connected to a reference potential. When forward voltage of each of diodes composing the diode string 55 is Vf and the number of the diodes composing the diode string 55 is m (m is an integer of 1 or more), a substrate bias voltage Vb of the depletion type transistor DNM1 is expressed by Vb=m×Vf. Since the forward voltage Vf of the diode has a negative temperature coefficient, the substrate bias voltage Vb has a negative temperature coefficient. Thereby a threshold voltage is provided with a negative temperature coefficient to cancel temperature characteristics of drain current I<SB POS="POST">D</SB>. <P>COPYRIGHT: (C)2013,JPO&INPIT |
