| 摘要 |
The constant voltage power source circuit which generates a predetermined constant voltage output Vcc by the use of power supplied from an in-vehicle battery via a power switch has a power transistor and an output voltage adjustment circuit. The output voltage adjustment circuit has a reference voltage generation circuit, a comparison amplification circuit, a resistance circuit network, and a nonvolatile second data memory selecting any of a plurality of on/off elements provided in the resistance circuit network and producing electric continuity of the selected on/off element. The constant voltage output Vcc is measured by an externally connected high accuracy voltmeter in the dispatch adjustment stage to be read out and stored via a serially connected external tool. Output voltage correction data are stored in the second data memory in such a manner as to set the external measurement voltage as a target voltage.
|
