전자부품 데이터시트 검색엔진 |
|
TEA2029 데이터시트(PDF) 7 Page - STMicroelectronics |
|
TEA2029 데이터시트(HTML) 7 Page - STMicroelectronics |
7 / 47 page Sync Level t S’ VPP Black Level Video Input Signal Composite Sync. Output Signal TH t r Frame Sync. Figure 5 V.2.1 - Black level locking 27 CC V + IC + ID ID = constant IC V N =2V VS1 VP V C27 VPP C1 -14 VN =2V IC Video Figure 6 The video signal is applied to Pin 27 through the coupling capacitor ”C27”. Since the sync pulse amplitude is generally equal to 1/3 of VPP (i.e. 66mV to 1V) and in order to obtain a good precision of the black level, the sync pulse should be amplified by a coefficient of - 14 before being applied to the comparator ”C1”. This comparator will charge the ”C27” capacitor as long as VS1 >VN ⋅ VS1 will stabilize at VN duringthe line flyback interval ”Tr” if the average charge of ”C27” capacitor is nil for one TH period. IC/ID is calculated such that the locking occurs at the middle of the back porch. 0 t t VS1 I C -5 µA t S t r VS1 VN (2V) t 1 t r t S = 2 + t S Figure 7 The ∆VS1 producedbyID during the line tracewhich is : 14 ⋅ ID ⋅ tA C27 must be equal to ∆VS1 during the time interval ”t1”, i.e. : 14 ⋅ IC ⋅ t1 C27 It follows that : IC ID = tA t1 = TH − tR tS + tR − tS 2 substituting TH =64 µs, tr =12 µs, tS =4.7 µs (which are standard and constant values) into above equation : IC ID = 6.23V V.2.1.1 - Application At IC =5 µA ⇒ ID =31µA - With C27 = 220nF, ∆VS will be 14 ⋅ 5 ⋅ 52 220 = 16mV which yields 0.8% maximum error in black level with respect to VN = 2V at the beginning of retrace time - Due to transposition on amplifier stage, the black level voltage on Pin 27 is equal to 2V. TEA2028 - TEA2029 APPLICATION NOTE 7/46 |
유사한 부품 번호 - TEA2029 |
|
유사한 설명 - TEA2029 |
|
|
링크 URL |
개인정보취급방침 |
ALLDATASHEET.CO.KR |
ALLDATASHEET 가 귀하에 도움이 되셨나요? [ DONATE ] |
Alldatasheet는? | 광고문의 | 운영자에게 연락하기 | 개인정보취급방침 | 링크교환 | 제조사별 검색 All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |