C). Adapter Trouble Shooting Chart & Bom - AOC LCD Monitor P/N : 41A50-144 Service Manual

2.3 Analog-to-Digital Converter
2.3.1 Pin Connection
The RGB signals are to be connected to the gmZAN1 chip as described in Table 8 and Table 9.
Table 8. Pin Connection for RGB Input with Hsync/Vsync
GmZAN1 Pin Name (Pin Number)
Red+(#95)
Red- (#94)
Green+(#91)
Green- (#90)
Blue+(#87)
Blue- (#86)
HSYNC/CS (#150)
VSYNC (#148)
Table 9. Pin Connection for RGB Input with Composite Sync
GmZAN1 Pin Name (Pin Number)
Red+(#95)
Red- (#94)
Green+(#91)
Green- (#90)
Blue+(#87)
Blue- (#86)
HSYNC/CS (#150)
The gmZAN1 chip has three ADC's (analog-to-digital converters), one for each color (red, green, and blue). Table 10
summarizes the characteristics of the ADC.
RGB Track & Hold Amplifiers
Band Width
Settling Time to 1/2%
Full Scale Adjust Range @ R,G,B Inputs
Full Scale Adjust Sensitivity
Zero Scale Adjust Range
Zero Scale Adjust Sensitivity
ADC+RGB Track & Hold Amplifiers
Sampling Frequency (fs)
DNL
INL
Channel to Channel Matching
Effective Number of Bits (ENOB)
Power Dissipation
Shut Down Current
(*) Guaranteed by design
The gmZAN1 ADC has a built-in clamp circuit. By inserting series capacitors (about 10 nF) the DC offset of an
external video source can be removed. The clamp pulse position and width are programmable.
Red
N/A (Tie to Analog GND for Red on the board)
Green
N/A (Tie to Analog GND for Green on the board)
Blue
N/A (Tie to Analog GND for Blue on the board)
Horizontal Sync
Vertical Sync
Red
N/A (Tie to Analog GND for Red on the board)
Green
When using Sync-On-Green this signal also carries the sync pulse.
N/A (Tie to Analog GND for Green on the board)
Blue
N/A (Tie to Analog GND for Blue on the board)
Digital composite sync. Not applicable for Sync-On-Green
Table 10. ADC Characteristics
MIN
160MHz
0.45V
+/-1 LSB
+/-1 LSB
20MHz
+/- 1.5LSB
+/- 0.5LSB
400mW
(**) Independent of full scale R,G,B input
CRT Signal Name
CRT Signal Name
TYP MAX
8.5ns Full Scale Input = 0.75V, BW=160MHz(*)
0.95V
Measured @ ADC Output (**)
For a larger DC offset from an external
video source, the AC coupling feature is
used to remove the offset.
Measured @ ADC Output
110MHz
+/- 0.9LSB fs = 80 MHz
fs = 80 MHz
7 Bits fin = 1MHz, fs=80 MHz Vin= -1db below
full scale=0.75V
fs=110 MHz, Vdd=3.3V
100uA
50
NOTE