| 摘要 |
PURPOSE:To easily convert the voltage level of an input/output signal between the in-circuit emulator side circuit of a 5V system by using an existing integrated circuit even when a target system side is constituted of a low voltage operating element. CONSTITUTION:A level conversion adaptor 10 in which a 5V system circuit 11 for emulating a microprocessor is applied to a low voltage system circuit 12 operated by a voltage lower than 5V by an in-circuit system is provided with as level control circuit 14 which limits signal line potential from the 5V system circuit 11 and arranged at every signal line, a voltage control circuit 16 which detects the source voltage of the low voltage system circuit 12 and controls the level control circuit 14, and a level booster circuit 15 which boosts the signal line potential from the low voltage system circuit 12, and limits the output voltage of a signal line for the 5V system circuit 11 lower than the source voltage of the low voltage system circuit 12 following the source voltage of the low voltage system circuit 12, and also, outputs the signal line potential recognizable by the 5V system circuit 11 to the 5V system circuit 11. |
