| 摘要 |
PURPOSE: An interface board apparatus for an information terminal is provided to externally supply a power when downloading a program in an information terminal and performing a diagnosis test. CONSTITUTION: A first connector(2) is connected with a PDA. Second and third connectors(4, 6) are connected with a PC. A first 2-pin header(10) is connected with the first connector(2) for downloading a program. A second through fourth 2-pin headers(12, 14 and 16) are commonly connected with a power terminal(8) and the first connector(2) through a first node(N1) and operate as a switch. 5V and 12V adjusting logic units(18 and 20) are connected with the third and fourth connectors(14, 16). A 3-pin header(22) selectively connects the first connector(2) and the 5V through 12V adjusting logic units(18, 20). An RS232 circuit(24) is commonly connected with the second and third connectors(4, 6) and the first connector(2) and convert a signal level. A 3.3V adjusting logic unit(26) is commonly connected with the second 2-pin header(12) and the first connector(2) and the RS232 circuit(24). First through fifth LED(LED1¯LED5) are provided to indicate an operation state of each line.
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