Samsung HPS5033X/XAC Service Manual

Also see for HP-S4253: Owner's instructions Manual de instrucciones

Contents

Circuit DescriptionSamsung Electronics 13-11■ Drive Waveform Specifications- Drive Waveform- Description of the function of each pulse1) Y Preset RA PulseThis is supplied to the first sub-field and erases the discharge status of the previous subfield.2) Y Main RA PulseDuring the Y Rising Ramp section, approximately 300V~350V (Vscan-h + Vset) of external voltage is supplied to the Y electrode,and a weak discharge is started when each gap voltage is equal to the discharge start voltage. While maintaining the weak dis-charge, as a whole, negative wall charges are accumulated on the Y electrode and positive wall charges on the X electrode andthe address electrode.During the Y Falling Ramp section, the negative wall charges accumulated on the Y electrode by the approximately 105V of X biasare used to erase the positive wall charges on the X electrode, and the address electrode maintains most of the positive wallcharges accumulated during the (0V) Rising Ramp section preparing for the next address discharge.3) Y Scan Pulse (Odd/Even)A scan pulse classifies the Y electrode into Odd and Even lines and selects FPC output electrodes sequentially (one line-at-a-time). At this time, Vscan is called the Scan Bias Voltage.A Vscan voltage of approximately -175 Volt (Vsc_1) is supplied to the electrode lines. For the other lines, -56 volt (Vsc_h is higherthan Vscan-l by 120V) is supplied. However, negative wall charges are accumulated on the Y electrode by the Ramp pulse, andpositive wall charges are accumulated on the address electrode, and the voltage applied to the cells, to which the Address pulse(70V~75V) has been applied, becomes higher than the discharge voltage. An address Discharge occurs as a result. Since theScan and Data pulse is applied one line at a time as above, the address time of PDP is very long.4) IDS Pulse (InDependent Sustain Pulse)Since an Odd Scan is performed first, the Odd line output sustains optical twice during the IDS section. At this time, a SustainDischarge does not occur for the Even line because the Even line is not scanned.5) CPS Pulse (ComPare Sustain Pulse)By floating the Odd line that caused the Sustain Discharge in the IDS section to the Vscan-h level, and introducing the SustainDischarge only for Even lines, it compensates for the optical output difference between the Even and Odd lines.6) CMS Pulse (ComMon Sustain Pulse)Actual optical is output during the common Sustain Discharge section.