Battery powered electronic device and control method therefor

摘要

A first control unit 110 and second control unit 120 are disposed to a portable data terminal 100 having a heavy load group 140 and light load group 150. The first control unit 110 detects the output voltage of a secondary battery 105 and controls power supply to the heavy load group 140 by switching a first switch S1. When the first control unit 110 stops power supply to the heavy load group 140, it outputs a low level control signal CC to the second control unit 120. The load of driving the second control unit 120 is designed to be smaller than the load of driving the first control unit 110. When the control signal CC is received, the second control unit 120 starts detecting the output voltage of the secondary battery 105, and stops power supply to the switch light load group 150 and first control unit 110 if the output voltage is detected to drop to a preset threshold voltage.