SDA9380-B21 Datasheet, PDF (16/72 Pages) Micronas – EDDC Enhanced Deflection Controller and RGB Processor

SDA 9380 - B21
Preliminary Data Sheet
System description
within 85ms to its final value. The high time is kept constant. The normal operating pulse ratio H/L is
either 45/55 or 40/60 (selectable by I²C). A watch dog function limits an increasing of the HD period
to max. +10%.
The implemented Black Switch-Off behaviour is defined by two I²C bits (BSO1, BSO0). When
enabled the signal at BSOIN (e.g. the supply voltage of the line output stage) is watched. If its level
does not come up to a defined threshold Black Swich-Off is started (see 11.2). At first the RGB out-
puts are switched to continuous blanking immediately and the vertical output signals are changed to
about 115..120% overscan. After a delay of 42 lines the picture tube capacitance is discharged with
a current of some mA. From now the vertical overscan rate is calculated depending on the actual
voltage at BSOIN to get the desired deflection angle. Three relations are selectable by I²C. After the
voltage at BSOIN is dropped down to about 20% of its initial value the output HD and the overscan
calculation may stop.
The protection circuit watches an EHT reference and the saw-tooth of the vertical output stage. If
the EHT succeeds a defined threshold or if the V-deflection fails (refer to 11.5) the related bit is set in
the status byte and the output PROTON goes High. The output HD is deactivated (H-level) immedi-
ately independent of the selected Black Switch-Off function.
HPROT:
input V_i < V2
V_i > V1
V2 ≤=V_i < V1
continuous blanking
HD disabled
operating range
VPROT:
vertical saw-tooth voltage
V_i < V1 in first half of V-period
or V_i > V2 in second half : HD disabled
The pin SCP delivers the composite blanking signal SCP. It contains burst (V_b), H-blanking HBL
(V_HBL)
can be
and selectable V-blanking
varied by I²C-Bus. For the
(control bit SSC). The phase and width
timing following settings are possible :
of
the
H-blanking
period
BD = 1
BD = 0, BSE = 0 (default value)
BD = 0, BSE = 1(alignment range)
SSC = 0
SSC = 1
: T_BL = 0
: T_HBL = t_f (H-flyback time)
: T_HBL = (4 * H_blanking-time + 1) / CLL
: T_DBL = (H_shift + 4 * H_blanking_phase
- 2*H_blanking_time + 45) / CLL
: T_BL = T_VBL during V-blanking period
: T_BL is always T_HBL
Micronas
5-8
2001-01-29