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approximately 1.0 V
BLH2 = 1 BLH1 = 0 for positive feedback polarity only: internal feedback reference voltage switched to
approximately 1.25 V
BLH2 = 1 BLH1 = 1 for positive feedback polarity only: internal feedback reference voltage switched to
approximately 1.5 V
1998 Dec 04 30
Philips Semiconductors Product specification
140 MHz video controller with I2C-bus TDA4886A
handbook, full pagewidth
START
LOAD PRESET CONTROL BITS
FPOL
PEDST
load from program
DISV = 1
ROM code or EEPROM
DISO = 1
BLH2
BLH1
LOAD FACTORY SETTINGS
GAIN
load from EEPROM
(CHANNEL 1, 2, 3)
FEEDBACK REFERENCES
(CHANNEL 1, 2, 3)
LOAD USER PRESET VALUES
load from EEPROM
CONTRAST
BRIGHTNESS
OSD CONTRAST
DEFLECTION
no
CONTROL
IC LOCKED
yes
DISV = 0
DISO = 0
DISPLAY NEW MODE(1)
DISO = 1
no
USER INPUT
yes
DISO = 0
RESPONSE TO USER INPUTS(2)
(CONTRAST, BRIGHTNESS, OSD CONTRAST)
DISO = 1
DEFLECTION
no
(1) Only synchronized video should CONTROL DISV = 1
be displayed. Each new mode IC LOCKED
can be displayed by OSD.
(2) Data transmission should be
yes MHB194
synchronized with vertical
blanking of the monitor.
Fig.14 I2C-bus control flow.
1998 Dec 04 31
Philips Semiconductors Product specification
140 MHz video controller with I2C-bus TDA4886A
12 TEST AND APPLICATION INFORMATION
contrast modulation input limiting input
handbook, full pagewidth
subcontrast setting
fast blanking
1 24
Application with integated
post amplifier, DC-coupled cathode
2 23
and negative feedback.
OSD
to cathode
3 22
inputs
90 V
4 21
BLACK LEVEL
5 20
RESTORATION
to cathode
6 19
Application with integated
TDA4886A
70 V
post amplifier, AC-coupled cathode
7 18 and black level restoration cicuit.
8 17
9 16
90 V
10 15
Application with discrete
post amplifier, DC-coupled
cathode and negative
11 14
feedback.
to cathode
12 13
8 V
MHB266
5 V
pull-up
resistors
I2C-BUS
output clamping
blanking
input clamping
vertical blanking
Fig.15 Basic applications for different kinds of post amplifiers with DC or AC coupling.
circuit and Figs 17 and 18 show the layout and mounting
12.1 Test boards
of the double-sided printed-circuit board. Most
For high frequency measurements a special test
components are of SMD type. Short HF loops and
application and printed-circuit board with only a few
minimum crosstalk between the channels and between
external components is built. It utilizes the internal positive
signal inputs and outputs are achieved by properly shaped
feedback of the output signals during output clamping with
ground areas.
control bit FPOL = 1. Figure 16 shows the test application
1998 Dec 04 32
Philips Semiconductors Product specification
140 MHz video controller with I2C-bus TDA4886A
1 k&!
handbook, full pagewidth
5.6 &!
FBL LIM
FBL 1 24
50 &!
OSD1 FB/R1 FB/R1
OSD1 2 23
solder pin
50 &!
channel 1
OSD2 VO1
OSD2 3 22 VO1
50 &!
3.3 10
1 k&!
pF k&!
5.6 &!
OSD3 VP1
OSD3 4 21
50 &!
100
150
0.47 µF
nF
pF
(63 V)
FB/R2 FB/R2
CLI
CLI 5 20
solder pin
50 &!
10 nF channel 2
VI1 VO2
6 19
VI1 VO2
50 3.3 10
5 k&!
150 pF
&! TDA4886A pF k&!
5.6 &!
VP VP2
J1
7 18
100
150
0.47 µF
100 100
0.47 µF
pF nF
10 nF
(63 V)
nF pF
(63 V)
VI2 FB/R3 FB/R3
VI2
8 17
solder pin
50
5 k&!
150 pF channel 3
&!
VO3
GND
J2
9 16 VO3
3.3 10
10 nF pF k&!
VI3 VP3 5.6 &!
VI3
10 15
100
150
50
5 k&!
0.47 µF
150 pF nF
pF
&!
(63 V)
HFB GNDX
J3
11 14
HFB
50
SCL
SDA
&! 150 10
12 13
pF nF
10 nF VPX
LIMAC
VP1 sense
50
10 k&!
&!
VP sense
10 k&!
VP
10 nF
SDA
GND
10 k&!
5 V
VINDC
SCL LIM
5 V
MHB267
Fig.16 Test board utilizing internal positive feedback only (FPOL = 1).
1998 Dec 04 33
Philips Semiconductors Product specification
140 MHz video controller with I2C-bus TDA4886A
handbook, full pagewidth 103
81
CLI OSD3 OSD2 OSD1 FBL 5.6 &!
1 k&!
10 k&!
50 &! 50 &! 50 &! 50 &! 50 &! VO1
3.3 pF
50 &! 1 k&!
-
U19
10 nF 0.47 µF
100 nF 150 pF
VI1 150 pF +
10 k&!
10 nF 5 k&!
3.3 pF
5.6 &!
J1
VO2
-
VI2
J2
0.47 µF
50 &!
100
TDA4886A +
150 pF
+
nF
5 k&!
0.47 µF
10 k&!
150 pF
-
VI3 5.6 &!
150 pF
50 &!
-
J3 VO3 0.47 µF
3.3 pF
10 nF
+
5 k&!
100 nF
150 pF
5.6 &!
50 &! 10 nF
HFB
50 &!
10 k&!
10 k&! 10 k&!
10 nF
SDA SCL
LIMAC
MHB268
Dimensions are in mm.
Fig.17 Top view of the printed-circuit board (for the bottom view see Fig.18).
1998 Dec 04 34
Philips Semiconductors Product specification
140 MHz video controller with I2C-bus TDA4886A
103
handbook, full pagewidth
81
100 pF
100 nF
100 nF
100 pF
MHB217
Dimensions are in mm.
Fig.18 Bottom view of the printed-circuit board (for the top view see Fig.17).
1998 Dec 04 35
Philips Semiconductors Product specification
140 MHz video controller with I2C-bus TDA4886A
12.2 Recommendations for building the application
board
" General
Double-sided board
Short HF loops by large ground plane on the rear
SMD components with minimum parasitics.
" Voltage outputs
Capacitive loads as small as possible
Be aware of internal output resistance
(typically 75 &!).
" Supply voltages
Capacitors as near as possible to the pins
Use electrolytic capacitors with small serial
resistance and inductance.
1998 Dec 04 36
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13 INTERNAL CIRCUITRY
SYMBOL AND
PIN CHARACTERISTIC WAVEFORM EQUIVALENT CIRCUIT
DESCRIPTION
1 FBL; fast open-circuit base
5 V
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