| 摘要 |
<p>PURPOSE:To provide a power supply circuit which is suitable for being used for a bard code scanner, capable of extending the life of a battery even when a relatively small capacity of battery is used by improving the utilization efficiency of a battery source 6. CONSTITUTION:This circuit comprises a DC-DC converter 5, which generates step-up voltage by boosting the output voltage of a battery source 6, a voltage regulator 3, which has an output terminal for supplying operation voltage to a load device, for example, a CCD line sensor for a bar code reader, a switch 4, which changes the output of the battery power source 6 and the stepped-up voltage selectively over to the input terminal of the voltage regulator 3 and supplies them to it, and a voltage detector 2, which detects the output voltage of the battery power 6, and when a voltage detector 2 detects the voltage below a specified value, it changes the switch 4 over to the stepped-up voltage side.</p> |
