參數(shù)資料
型號(hào): GS4901BCNE3
廠商: Gennum Corporation
英文描述: SD Clock and Timing Generator with GENLOCK
中文描述: 統(tǒng)計(jì)時(shí)鐘和定時(shí)發(fā)生器鎖相
文件頁(yè)數(shù): 38/95頁(yè)
文件大小: 898K
代理商: GS4901BCNE3
GS4901B/GS4900B Preliminary Data Sheet
37703 - 0
April 2006
38 of 95
5. For blanking-based input references, the device will advance all line-based
output timing signals by 1 line if the value programmed in the H_Offset register
is greater than the number of output video clock cycles from the start of H
Sync to the end of active video (Hsync_to_EAV) + 20. The value of
Hsync_to_EAV is reported in register 51h and changes according to the output
VID_STD selected. The user may compensate for this advance by adding 1
line to the desired vertical offset before loading this value into the register. In
addition, the internal V_lock and F_lock signals reported in bits 3 and 4 of
register 16h will be LOW when H_Offset = Hsync_to_EAV + 21 only, although
the device will remained genlocked. The user may choose to mask these lock
signals such that the device will continue to report genlock under this
condition.
6. The offsets that occur as described in notes 1-5 are independent of one
another and must be accounted for as such.
3.2.1.2 Freeze Mode
When the device is in Genlock mode and the input reference is removed, the
GS4901B/GS4900B will enter Freeze mode. The behaviour of the device during
loss and re-acquisition of an input reference signal is described in
Section 3.5.3 on
page 44
.
In Freeze mode, the frequency of the output clock and timing signals will be
maintained to within +/- 2ppm. This assumes a loop bandwidth of 10Hz. Also, if the
frequency of the 27MHz reference crystal shifts while in Freeze mode, the
frequency of the output clock and timing signals will shift as well.
3.2.2 Free Run Mode
The GS4901B/GS4900B will enter Free Run mode when the GENLOCK pin is set
HIGH by the application layer. In this mode, the occurrence of all frequencies is
based on the external 27MHz reference input. Therefore, the frequency of the
output clock and timing signals will have the same accuracy as the crystal
reference.
If operating in Free Run mode, using a more accurate crystal (e.g. 10ppm) ensures
more accurate clock and timing signals are generated.
NOTE: In Free Run mode, the audio clocks of the GS4901B will remain genlocked
to the video clock.
Figure 3-2
summarizes the differences in output accuracy in each mode of
operation. Assuming a crystal reference of +/-100ppm, in Free Run mode the
frequency of the output clock and timing signals will be as accurate as the crystal.
In Genlock mode the frequency will be as accurate as the input reference
regardless of the crystal accuracy. In Freeze mode, the frequency of the output
clock and timing signals will be maintained to within +/- 2ppm.
相關(guān)PDF資料
PDF描述
GS4910B HD/SD/Graphics Clock and Timing Generator with GENLOCK
GS4910BCNE3 HD/SD/Graphics Clock and Timing Generator with GENLOCK
GS4911B HD/SD/Graphics Clock and Timing Generator with GENLOCK
GS4911BCNE3 HD/SD/Graphics Clock and Timing Generator with GENLOCK
GS4915 CONN,S/R,8 POS,254C-08-1, CLOSED END STRAIN RELIEF COVER
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
GS4910B 制造商:GENNUM 制造商全稱:GENNUM 功能描述:HD/SD/Graphics Clock and Timing Generator with GENLOCK
GS4910BCNE3 功能描述:IC RE-TIMER RoHS:是 類別:集成電路 (IC) >> 時(shí)鐘/計(jì)時(shí) - 專用 系列:- 標(biāo)準(zhǔn)包裝:1,500 系列:- 類型:時(shí)鐘緩沖器/驅(qū)動(dòng)器 PLL:是 主要目的:- 輸入:- 輸出:- 電路數(shù):- 比率 - 輸入:輸出:- 差分 - 輸入:輸出:- 頻率 - 最大:- 電源電壓:3.3V 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:28-SSOP(0.209",5.30mm 寬) 供應(yīng)商設(shè)備封裝:28-SSOP 包裝:帶卷 (TR) 其它名稱:93786AFT
GS4911ACNE3 制造商:Rochester Electronics LLC 功能描述: 制造商:Gennum Corporation 功能描述:
GS4911B 制造商:GENNUM 制造商全稱:GENNUM 功能描述:HD/SD/Graphics Clock and Timing Generator with GENLOCK
GS4911B_09 制造商:GENNUM 制造商全稱:GENNUM 功能描述:HD/SD/Graphics Clock and Timing Generator with GENLOCK