| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a transmitter, an interface device, and an in-vehicle communication system which restrain duty variation of input signals and output signals due to variation of power source voltage. <P>SOLUTION: A transmitter 10 comprises: a condenser 105 from one end of which charging voltage Va is extracted; a first constant current source 103 which generates a charging current I1 of the condenser 105; a second constant current source 104 which generates a discharge current I2 of the condenser 103; charging and discharging current control parts (101, 102, and 106) which perform charging and discharging control of the condenser 105 based on the comparison result of a logic level of a transmission input signal IN and the charging voltage Va and the reference voltage Vref; output steps (109-116) which generate transmission output signals OUT whose slew rate is set according to the charging voltage Va and whose signal amplitude is set according to the output side power source voltage V2; a reference voltage generation part 107 which fluctuates the reference voltage Vref depending on the output side power source voltage V2; a constant current control part 108 which fluctuates each current value of the charging current I1 and discharging current I2 depending on the reference voltage Vref. <P>COPYRIGHT: (C)2012,JPO&INPIT |
