MB87P2020 Datasheet, PDF (218/356 Pages) Fujitsu Component Limited. – Colour LCD/CRT/TV Controller

MB87J2120, MB87P2020-A Hardware Manual
The duration of the appropriate phases calculates as follows:
15. Start-up phase:t_start = t_bper · 8
16. Ionization phase:t_ion = t_bper · 4 · IGNITE
17. Pause:t_pause = t_bper · 4 · PAUSE
18. Flash phase:t_flash = t_bper · 4 · FLASH
The fifth phase equals to the remaining off time until the next rising edge of the synchronisation signal
Note: If FLASH duration exceeds display frame duration the next synchronization will be dropped and lamp
is off the next period after previous FLASH duration is ended. This could be result in flickering or malfunc-
tion of the lamp.
2.3 Pulse shape of FET1 and FET2
The following figure shows the pulse shape of pulses, which have to be generated during Ionisation and
Flash phase.
FET1
FET2
7t _bper
7t _bper
1t _bper
1 cycle
Figure 2-2: Timing definition of FET control signals
1t _bper
If the end of a phase is reached during a high period of a pulse, a shortened pulse has to be generated as
shown in the following figure.
FET1
FET2
7t _bper
4t _bper
1t _bper
3/4 cycle
Figure 2-3: Timing definition of FET control signals for fractured number of cycles
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