- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄385549 > MAX7461 (Maxim Integrated Products, Inc.) Loss-of-Sync Alarm PDF資料下載
參數(shù)資料
| 型號： | MAX7461 |
| 廠商： | Maxim Integrated Products, Inc. |
| 英文描述： | Loss-of-Sync Alarm |
| 中文描述： | 同步丟失報警 |
| 文件頁數(shù)： | 4/7頁 |
| 文件大?。?/td> | 500K |
| 代理商： | MAX7461 |
M
Detailed Description
The MAX7461 single-channel LOS alarm is ideal for any
video system needing to verify the presence of a video
source. The device accepts an AC-coupled CVBS, Y,
or any video signal with sync, and pulls
LOS
low when
no composite sync signal is detected for more than the
LOS detect time (3.4ms, typ) at the input (IN).
Clamp
The MAX7461 features an input clamp that corrects any
DC shift, on a line-by-line basis. The external AC-cou-
pling capacitor provides DC isolation for the input.
Lowpass Filter
The MAX7461 integrates a lowpass filter for enhanced
sync detection. The lowpass filter prevents false sync
detection by reducing color burst, chroma, and noise.
Sync Detector/LOS Filter
The sync detector looks for sync pulses greater than
the minimum sync voltage (0.13V
P-P
). If the detector
does not detect any sync pulses for 3.4ms (typ), the
LOS filter pulls
LOS
low. After detecting sync for at
least 2.2ms (typ), the LOS filter returns
LOS
to a high-
impedance state.
LOS
is an open-drain output.
Connect a 1k
pullup resistor between
LOS
and V
CC
.
Power-On Reset (POR)
At power-up,
LOS
is pulled low and the MAX7461
checks for 2.2ms (typ) of valid sync pulses before
releasing
LOS
.
LOS
remains high impedance while a
valid sync signal is detected at the input.
Applications Information
Input Considerations
Use 0.1μF ceramic capacitors to AC-couple the input.
The input cannot be DC-coupled. The input capacitor
stores a DC level so that the video signal is clamped to
an appropriate DC voltage for proper sync detection.
Power-Supply Bypassing
Careful PC board layout is important for optimal system
performance. Do not use wire-wrapped boards or
breadboards. When possible, use a multilayer board
with a dedicated low-inductance ground plane and
supply plane. Connect all GND inputs to a single
ground plane and V
CC
to a single-supply plane.
Bypass V
CC
to GND with a 0.1μF capacitor.
Wired-OR Application
The
LOS
open-drain output allows the MAX7461 to be
used in wired-OR applications as shown in the automo-
tive RSE typical application diagram of Figure 1.
Chip Information
PROCESS: BiCMOS
Loss-of-Sync Alarm
4
_______________________________________________________________________________________
Pin Description
PIN
NAME
FUNCTION
1
IN
Video Input.
Accepts CVBS, luma (Y), or any video input with sync.
AC-couple IN with a series 0.1μF
capacitor.
2, 3
GND
Ground
4
LOS
Loss-Of-Sync Output (Open Drain).
LOS
is in high impedance when sync pulses are detected, and is
pulled low
when no horizontal sync signal is detected for more than the LOS detect time.
LOS
returns
high when sync pulses are detected for more than the LOS release time.
Connect a 1k
pullup resistor
from
LOS
to V
CC
.
5
V
CC
Power-Supply Input.
Bypass to GND with a 0.1μF capacitor.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MAX7461EUK | Loss-of-Sync Alarm |
| MAX7481 | Bidirectional Video Filters/Buffers for Composite and S-Video Portable Media Devices |
| MAX7482 | Bidirectional Video Filters/Buffers for Composite and S-Video Portable Media Devices |
| MAX7501SE | LOW-POWER, MONOLITHIC,CMOS ANALIOG MULTIPLEXERS |
| MAX7501SQ | LOW-POWER, MONOLITHIC,CMOS ANALIOG MULTIPLEXERS |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| MAX7461EUK | 制造商:Maxim Integrated Products 功能描述:LOSS-OF-SYNC ALARM - Rail/Tube |
| MAX7461EUK+ | 制造商:Maxim Integrated Products 功能描述:LOSS OF SYNC ALARM 5PIN SOT-23 - Rail/Tube |
| MAX7461EUK+T | 功能描述:視頻 IC Loss-Of-Sync Alarm RoHS:否 制造商:Fairchild Semiconductor 工作電源電壓:5 V 電源電流:80 mA 最大工作溫度:+ 85 C 封裝 / 箱體:TSSOP-28 封裝:Reel |
| MAX7461EUK-T | 功能描述:視頻 IC RoHS:否 制造商:Fairchild Semiconductor 工作電源電壓:5 V 電源電流:80 mA 最大工作溫度:+ 85 C 封裝 / 箱體:TSSOP-28 封裝:Reel |
| MAX7462USA | 功能描述:有源濾波器 RoHS:否 制造商:Maxim Integrated 通道數(shù)量:1 截止頻率:150 KHz 電源電壓-最大:11 V 電源電壓-最小:4.74 V 最大工作溫度:+ 85 C 安裝風格:Through Hole 封裝 / 箱體:PDIP N 封裝:Tube |
發(fā)布緊急采購，3分鐘左右您將得到回復。