ViewSonic N3260w-1NT Service Manual page 13

AV (Video) Input circuit (AV,S,YPbPr,PC,HDMI ):
• AV IN:AV1、AV2、S1、S2、YPbPr1 、YPbPr2 、HDMI、PC
•AV BOX AV1 or AV2 Input:
• Composite video output signal of external AV1 or AV2 device respectively input IC U1 Video/Audio
SWITCH Input port PIN 65,71 and switch signal with other Video Source in CPU controlled inner switch circuit.
• U1 Composite video output:
After switching with other Video Signal source, output from U1 PIN 60 (signal mark CYOUT 2) goes through Q38 Video
buffer (signal mark CVBS_EX) and input U38 Scaler IC EX-52 input jack (Pin 243) (CVBS2)directly.
Switches with other input signals in U38 inner switch circuit.
• PIP/POP mode
U3 PIN 56 output AV composite image signal (CYOUT1) via Buffer Q36 translate into CVBS_7 signal then
input U30 SA7117 Video decode PIN L3 to proceed PIP/POP function in PIP/POP mode .
• S 、Composite video Terminal.
• U3 S1 or S2 input
S video include Y,C siganl . S1Y1 & C1 input respectively U3 PIN67,69 .S2 Y2 &C2 input respectively
from U3 PIN73,75.Switch signal with other Video Source in U1 inner switch circuit.
• U3 S Output
S(Y/C) output respectively from PIN56 and 55 .Y singal via Buffer(Q29) translates into LUMA_7 than input
U30 SA7117 Video decode PIN k2.
• PIP/POP mode
Via Buffer Q36,C signal (PBOUT2) translate into CHROMA_7 and input U30 SA7117 Video decode PIN
H2 to proceed PIP/POP function in PIP/POP mode .
• HDTV: Receives outside AV DEVICE Component Video signal .YIN_1,PBIN_1,PRIN_1 input respectively U1
PIN21,23,25 and Switch signal with other Video Source in U1 inner switch circuit than Y via Q37 Video buffer
input U38 EX-52 PORT Y_G1(PIN246),Pb viaQ40 Video buffer input U38 EX-52 PORT PB_B1(PIN232),Pr via
Q39 Video buffer input U38EX-52 PORT PB_R1(pin225) and Switch signal with other Video Source in EX_52 .
• HDMI: Receives outside AV DEVICE HDMI Digital , U53 Sil9011 translate Digital Video signal decode into
24 bits Digital RGB signal DIN[0:23],than input U38 EX-52 Digital PORT DIN[0:23] and switch with other Audio
source in EX-52 .
• PC(VGA) signal includes: R、G、B、HS (Horizontal sync signal)、VS (Vertical sync signal), R transmits to U38
EX-52 PORT PR_R2_G1(PIN226)、G transmits to U38 EX-52 PORT Y_G2(PIN248)、B transmits to U38 EX-52
PORT PB_B2(PIN233) and switch with other EX-52 inner signals. HS(Horizontal sync signal) transmits to U38
EX-52 PORT AIN_HS(PIN10),VS (Vertical sync signal ) transmits to U38 EX-52 PORT AIN_VS(PIN11).
• U38 EX-52 transmits digital Video via LVDS (TXOUT0:3+,TXOUT0:3-) to PIN Set J10 and show out the image.
ViewSonic Corporation
12
Confidential - Do Not Copy
(AS block diagram 4)
N3260w_N3760w_N4060w
N3260wb_N3760wb
-1NT