PORTABLE EQUIPMENT AND ITS DRIVING METHOD

• Main Author: OOTSUKA YOSHIAKI
• Format: Patent
• Language: English
• Published: 02.07.1999
• Edition: 6
• Subjects: ADVERTISING; ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICESUSING STATIC MEANS TO PRESENT VARIABLE INFORMATION; CRYPTOGRAPHY; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; DISPLAY; EDUCATION; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; SEALS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

PROBLEM TO BE SOLVED: To reduce the power consumption of an LCD as the rest of a battery becomes small and to save the power of the portable equipment by allowing a CPU to read in the value of the battery voltage and decrease the vertical synchronizing frequency of an LCD module. SOLUTION: The CPU 100 outputs an A/D converter channel select signal to select a terminal of an A/D converter 200 and read the voltage of the battery 108 through a battery power line 109. The A/D converter 200 sends the battery voltage value to the CPU 100 through an A/D data output signal. The CPU 100 retrieves timing data to the LCD module corresponding to the sent voltage value data. Then the CPU 100 judges from the voltage value whether or not the timing needs to be changed. When the timing needs to be changed, the CPU 100 changes a register of an LCD controller 101 to change the timing of the LCD module 102.